A veiled attack on substantive fairness in Canada?

The substantive right to a fair trial must be distinguished from its procedural correlatives such as the right to confront witnesses and to present a defence. The procedural rights may be subject to balancing against competing rights, but the substantive right to a fair trial is regarded as absolute in some jurisdictions.

The Supreme Court of Canada has recently not distinguished procedural fairness from substantive fairness, and by a majority it has treated the apparently composite right to a fair trial as something that can be balanced against competing rights: R v NS, 2012 SCC 72 (20 December 2012).

The implications of the case extend far beyond its facts, which raised the issue of how a court should decide whether to permit a witness to wear a niqab (face covering). There is obviously a range of potential answers: always permit it (Abella J), never permit it (LeBel and Rothstein JJ), and sometimes permit it (McLachlin CJ, Deschamps, Fish and Cromwell JJ).

The majority held that if a right competed with the defendant's righs to confront witnesses and to present a defence, and if there was no way to give full effect to all these rights, there would then be a balancing. This would require some limitation of rights, perhaps but not necessarily on both sides.

In including the substantive fair trial right in this balancing exercise the majority have declined the opportunity to use it as the ultimate criterion. Contrasting views of the importance of substantive fairness are found in cases from other jurisdictions, not considered in this case: R v A (No 2) [2001] UKHL 25, [2002] 1 AC 45 (HL) (mentioned here on 4 September 2004, and see also the discussion of Randall v R (Cayman Islands) [2002] UKPC 19 and of other relevant cases here on 16 September 2010, R v Davis [2008] UKHL 36 noted here as the second entry for 19 June 2008, and the still-obscure position in Gäfgen v Germany [2010] ECHR 759 noted here on 25 June 2010.

NS appears to establish that in Canada the right to a substantively fair hearing is not absolute. The minority judgments illustrate arguments that now must be regarded as wrong. McLachlin CJ summarised her position for the majority [34]:

"... The question is whether the salutary effects of requiring the witness to remove the niqab, including the effects on trial fairness, outweigh the deleterious effects of doing so, including the effects on freedom of religion ... ."

This assumes that the right to a fair trial may not outweigh freedom of religion. And at [46]:

"I have proposed that courts should deal with the conflict between rights in cases such as this by finding a just and appropriate balance between freedom of religion on the one hand and fair trial rights on the other. The result is that where a niqab is worn because of a sincerely held religious belief, a judge should order it removed if the witness wearing the niqab poses a serious risk to trial fairness, there is no way to accommodate both rights, and the salutary effects of requiring the witness to remove the niqab outweigh the deleterious effects of doing so."

The deleterious effects are the limitation on freedom of religion, the inhibition of complainants and the consequential escape of offenders from justice. Obviously those are hugely important considerations. The salutary effects are preventing harm to the fair trial interest and safeguarding the repute of the administration of justice. The need to find a balance between the deleterious effects and the salutary effects recognises that the salutary effects do not necessarily outweigh the deleterious effects.

It may be that when unfairness goes beyond procedural unfairness and becomes substantive unfairness, it will always outweigh the deleterious effects of requiring a competing right to yield. But that is not clearly stated as the ratio of this case. On its face the majority reasoning has an unpleasant "ends-justify-the-means" blemish.

Although this case is newsworthy for its decision about the wearing of niqabs and the place of religious expression in the courtroom, it has much wider implications. In a contest of competing rights, the majority judgment potentially diminishes the right to a fair hearing in Canada.

The obligation to select an impartial jury

Jury vetting was last week the subject of three decisions of the Supreme Court of Canada. All three inevitably focus on trial fairness.

R v Davey, 2012 SCC 75 (21 December 2012) concerns personal opinions sought by the Crown from police officers about the suitability of prospective jurors, recorded in an annotated list that was not disclosed to the defence, and a trial in which two of the chosen jurors had been marked as "good" and "ok".

Karakatsanis J for the Court observed that this case did not involve police access to any database or any police investigation. However she held there should be no systematic distribution of jury panel lists to police services for comment regarding the suitability of potential jurors [8]. State resources should not be used by the Crown to enable it to choose a jury that may be perceived to be favourable to the Crown. Targeted consultation with a limited number of individuals working on the case with the prosecution is acceptable if it is to discuss concerns as to partiality, eligibility or suitability of a prospective juror [9], but any information relevant to the selection process must be disclosed to the defence.

Where the information that should have been disclosed had not been disclosed, the question was whether there was a real possibility that the jury was not impartial or whether, had it been disclosed, a differently constituted jury would have been selected. If not, the further question was whether the circumstances created an appearance of unfairness such as to interfere with the administration of justice or such as to so offend the community's sense of fair play and decency that the proceedings should be set aside as a miscarriage of justice [24], [54], [74].

The selection process must ensure an independent, impartial and competent jury [30], and neither party has the right to select a jury or a positive power to shape a jury.

Although there had been a breach of the disclosure requirement here, in the circumstances there was no unfairness and the appeal was dismissed. The reasoning is fact-dependent and the Court defers, with only a slight weakness appearing in [72] where mention is made of the defence not having used all its peremptory challenges.

An interesting and undecided point was what standard would be on the Crown if it had the burden of showing that the jury had been impartial or that there was no appearance of unfairness such as to amount to a miscarriage of justice [55, footnote 5]. Karakatsanis J thought it may be the balance of probabilities. Arguably there is no need for a further legal burden: on appeal the appellant has the legal burden and that should be that. But the point here is that a new issue – factual impartiality - is brought into play, as a sort of defence to the appeal. However you might well think that since the possibility that a different jury might have been chosen is not necessarily related to the real harm of a biased jury, it is inappropriate to make that a criterion for a successful appeal. Therefore it would be preferable to take the more conventional approach of requiring the appellant to succeed on either (i) establishing a real risk that the chosen jury was not impartial, or (ii) establishing the appearance of unfairness. No question of a burden on the Crown would then arise.

The second vetting case did involve use of a police database: R v Emms, 2012 SCC 74 (21 December 2012). Here Moldaver J delivered the judgment of the Court. Information obtained at the request of the prosecutor and not disclosed to the defence concerned whether prospective jurors had criminal convictions or were in other respects "disreputable persons". Although the Crown was entitled to have inquiries made for the purpose of checking eligibility to serve, which included absence of disqualifying convictions, or for other information to support challenge for cause, and was obliged to disclose that information to the defence, it was not entitled to have checks on the further question of whether a prospective juror might be disreputable. But if information on disrepute came to light it should be disclosed to the defence if the Crown considered it to be relevant to the jury selection process [48]. Here the appellant failed to establish that, had the information been disclosed, there was a reasonable possibility that a differently constituted jury would have been chosen [22]-[29]. Neither was the departure from what was, by the time of the trial, a required procedure, sufficient in the circumstances to amount to a serious interference with the administration of justice, or to offend the community's sense of fair play and decency to the extent of being a miscarriage of justice [43]-[49].

The third, and leading, decision (first in time and applied in Emms and Davey) is R v Yumnu, 2012 SCC 73 (21 December 2012). Moldaver J, for the Court, set out the fundamentals applicable to when police databases may be used in jury vetting. Nothing could do more harm to the criminal justice system than the Crown and the police joining forces to obtain a favourable jury [37]. The Crown has the responsibility, as an officer of the court, to ensure every defendant receives a fair trial [40]. Randomness and representativeness are two qualities looked for in juries, and checking that gives rise to an appearance of stereotyping through the use of peremptory challenges could be seen as incompatible with the Crown's responsibility [40]. The privacy of prospective jurors is also important [43], although there are countervailing interests in ensuring eligibility and impartiality [45]. Limited use of police databases is permissible to check for grounds for challenge for cause [50]-[51]. Sometimes those checks may reveal other relevant information. Any information that is relevant to jury selection (outside matters of public knowledge or feelings, hunches, suspicions, innuendo or other amorphous information [64]) must be disclosed to the defence [55], [63].

There is also a duty on defence counsel to disclose information where there is good reason to believe a potential juror may be ineligible or may not be impartial [66]-[67].

Importantly, jury selection is not a game and winning or losing are concepts that ought not to be associated with it. The aim is to obtain an impartial jury: "The jury does not belong to the parties; it belongs to the people." [71].

Attempts by one side or another to obtain a favourable jury are inimical to the right of every person who is charged with an offence to be tried by an independent and impartial tribunal [72].
In these kinds of cases the appellant must establish that the Crown did not disclose information that it should have disclosed, and that if disclosure had been made there is a reasonable possibility that the jury would have been differently constituted [75]. The point mentioned by Karakatsanis J in Davey above, about the Crown showing that nevertheless the jury was impartial, was left open for another day [76].

On the facts here the appellant failed to establish a real possibility that a differently constituted jury would have been selected [77]. And on the alternative ground of appearance of unfairness [79] what happened here was neither a serious interference with the administration of justice nor was it such an offence to the community's sense of fair play and decency that there was a miscarriage of justice [89].

Again one might object that the possibility that a different jury would have been selected is an inappropriate requirement: even if the defendant had known what the Crown knew about the juror, the defendant may have already run out of challenges at the critical moment.

This separation of two aspects of unfairness – actual unfairness and the appearance of unfairness – gives rise to an interesting interpretive question for those who will have to apply s 232 of the Criminal Procedure Act 2011 [NZ]. There, "an unfair trial" may be construed as including a trial that appears to have been unfair, although this is far from certain.

The Supreme Court of New Zealand has taken a rather more constrained approach to the Crown's disclosure obligations in relation to jury vetting: Gordon-Smith v R [2009] NZSC 20 (23 March 2009, noted here). The dissent of McGrath J in that case is in line, concerning what needs to be disclosed to the defence, with the Supreme Court of Canada's statement of the law. The majority however went so far as to give the impression there might be some justification for limiting trial fairness:

"[18] It is always important that there be no justified perception or real risk of unfairness in any respect, if that can be avoided consistently with other relevant features. The privacy and security of jurors is such a feature. ..." [emphases added]

But Gordon-Smith was decided in a torrid atmosphere of public unrest at the perceived and potential misuse of jury panel lists especially by unrepresented defendants.

This is not to say that the Supreme Court of Canada is not also capable of wobbling a bit when it comes to trial fairness for the defendant, as shall be seen when I come to discuss veiled witnesses. However as far as jury vetting goes, the cases invite discussion of when the court should react to procedures that, although improper, had no discernible effect on the result of a trial, and if reaction is appropriate, what remedy should be given to a defendant when those at fault are out of the court's reach.

A note on substantive trial fairness

An issue of trial fairness is raised if a judge fails to address an element of an offence. If an element is overlooked, but the evidence overwhelmingly proves that element, does it matter that the fact-finder did not make a finding on it?

The significance of the omission will need to be assessed in the circumstances of each case. Trial fairness is not simply a procedural matter. If it was, the answer would be the same in every case. But trial fairness has substantive meaning: the law must be accurately applied to facts determined impartially.

In R v Khawaja, 2012 SCC 69 (14 December 2012) an element of the offence had been overlooked, but the error did not affect trial fairness:

"[93] This is an exceptional result, appropriate in the exceptional circumstances of this case. Generally speaking, if an appellate court finds that the offence for which an appellant was convicted includes an additional essential element, fairness would require ordering a new or directed trial. In this particular case, however, this Court can be confident that the appellant suffered no prejudice deserving of a new trial only because the evidence on the additional element of the offence was overwhelming, as indeed the trial judge found, and it is plain that the appellant's strategy would not have changed had the element been recognized at trial."

A misunderstanding of this would be that the ends justified the means: if the person was obviously guilty the error could not affect the fairness of the trial. What the Court means here is that the error did not affect the impartial determination of the facts because the defendant would not have conducted his defence differently had the error not occurred, and the defendant was not deprived of a real chance of a more favourable outcome.

Bain, Binnie, Fisher, Bayes – how should judges reach conclusions?

Once again out little nation is divided over the Bain case and its consequences. The current controversy is over whether the report by retired Canadian Supreme Court Justice Ian Binnie should be accepted or whether its review by retired New Zealand High Court judge Dr Robert Fisher QC has cast doubt on its conclusions.

We have seen here recently how appellate judges on the same court can differ sharply over what conclusions can be drawn from the evidence in a case. Is there a right way to arrive at conclusions from facts?

In trials juries are given little guidance on how to reason, other than being told that the drawing of inferences is a process of using logic and common sense, something people do all the time in their daily lives. It is assumed that people have an innate ability to reach proper conclusions. This assumption must be correct. We tend to be right more often than we are wrong, but without examining why.

Judges have to give reasons for their decisions. The process of articulating reasons imposes a discipline on judicial thinking, and until that process is completed a judge may not know what conclusion is going to be reached. An echo of this is the instruction to jurors to keep an open mind while evidence is being given.

Bayesian analysis is useful in revealing or guarding against errors of logic when inferences are drawn from facts. Dr Fisher has used this in his report. This does not mean that Ian Binnie was wrong to not use it in his. Most people have no idea what Bayes' Theorem is and they infer correct conclusions without using it. The interesting question is whether Dr Fisher has revealed any error of logic that was sufficient to make Ian Binnie's conclusions wrong.

My assessment is that the only candidate for being an error of this significance is Dr Fisher's claim that Ian Binnie failed to consider the evidence cumulatively as opposed to by taking each item at a time. Ian Binnie has denied, in an email to the Minister of Justice that has been published, that he made this error.

It would be astonishing if Ian Binnie had made this mistake. Judges habitually stand back after evaluating the probative value of particular facts and look at the overall picture. That is done to enable a conclusion to be drawn from the combination of the probative values of the facts. This process is what is done instinctively when people exercise their judgment.

There are all kinds of influences, revealed by psychologists, which can cause people to make mistakes. A Bayesian approach to inference drawing can counteract those, but its best application requires extensive statistical information, far beyond what is usually available in court cases.

Nearly all judicial decisions are made only on the balance of probabilities. This standard recognises that we can seldom be certain we are right, and that in the interests of finality a decision on the balance of probability is good enough. Hugely important decisions are regularly made in the courts on that basis.

It is significant that Dr Fisher has not endeavoured to decide whether Ian Binnie's conclusions were right or wrong, but that he correctly restricted his report to Ian Binnie's method. Plainly, if Dr Fisher were to go further in a subsequent report, he would apply the Bayesian approach. But that should lead to the same conclusions that Ian Binnie reached unless radically inappropriate assessments of likelihood were made by Ian Binnie over critical facts to such an extent as to influence the result of considering the combined probative values of all the relevant facts.

I was surprised when reading Ian Binnie's report at how he treated the evidence of the luminol footprints. Depending on the length of those footprints, they could have removed the case from being an exercise in assessing probabilities and made this a case of direct evidence of innocence. That was recognised in the Privy Council hearing, as both sides agree. However Ian Binnie has been generous to the prosecution by recognising some doubt over the accuracy of the measurement made by the police scientist of the footprints on the carpet at the scene.

Whether the measurement could really have been susceptible to error to an extent sufficient to cast doubt on who left it there is a matter of judgment for those who have looked at the evidence that was given on this point.

In his conclusions on the footprint evidence at para 263 of his final report, Ian Binnie appears to accept a margin of error in the measurement carried out by the police scientist at the scene of about 5mm. Taking this at its most favourable to the prosecution, the print at the scene may have been 285mm, and David’s 300mm foot may leave a print that was 295mm. That is a difference of 1cm. In tests referred to at para 252 it was noted that carpet prints were never less than the actual foot length, so it seems extremely generous to the prosecution to accept that David may have left a print that was 295mm, especially if the police scientist’s notes did not record uncertainty or imprecision when the length was measured as 280mm. In any event, even a difference of 1cm (more likely 1.5cm, and even more likely greater than that) marks a clear difference between David and Robin’s footprints. The defence expert said that David’s foot could not have left the print found at the scene (again para 252), and Ian Binnie recommended without hesitation that these results be accepted (para 257).

At the measured 280mm the footprints were exact matches for prints that would be left by Robin Bain's foot.

It is in my opinion appropriate for a fact-finder to accept that David’s foot did not make these prints. The footprints are direct evidence of who the killer was.

The other evidence in the case is consistent with guilt or with innocence. Taken together, in my opinion, and remember I am for the moment ignoring the footprint evidence, the other evidence amounts to proof beyond reasonable doubt that David was guilty. In reaching that conclusion I use a Bayesian approach and assess probabilities on a commonsense basis as best as I can. That method is acceptable in the absence of more formal statistical data. This is why it was reasonable for the Robin Bain supporters to argue that David was guilty. It is also why the Court of Appeal was right in 2003 to conclude that on the evidence before it David was guilty. The footprint evidence in its final form was unknown then (see para 156 of the Court of Appeal’s judgment). The Privy Council corrected the Court of Appeal on the legal grounds of how an appellate court should deal with conviction appeals: not by coming to its own verdict but, if it finds an error that could have affected the fact finding at trial, by ordering a retrial if the prosecution wanted one. At the Privy Council the footprint evidence was approaching its final form and that is why the Board indicated that it was critical evidence, and both sides accepted that.

When the final form of the footprint evidence is included in the assessment it overwhelms the cumulative effect of the other evidence, and requires the reverse conclusion. Now, it can be concluded that what was unlikely did in fact happen. And now David’s innocence is proved beyond reasonable doubt. In Bayesian terms the likelihood ratio is so strongly in favour of the hypothesis that David is innocent that there is no real possibility that he is guilty.

If all the other evidence in the case proved guilt to a probability of 0.95, the footprint evidence would reduce that to 0.80; if all the other evidence in the case proved guilt to a probability of 0.99, the footprint evidence would reduce that to 0.96. So when I say there is "no real possibility that he is guilty" I do acknowledge that 0.96 may be proof beyond reasonable doubt for some people. The estimates of probabilities are used as follows. The first question is, what is the probability of getting these footprints, on the assumption that David is guilty? Experiments showed that it is most unlikely that David's foot could have left prints of that size, so this probability might be assessed as, say, 0.25, which seems rather generous to the prosecution. The second question is, what is the probability of getting these footprints, on the assumption that David is innocent? Because they fit well with the size of Robin's feet, this probability may be close to 1. The third question is, what is the ratio of these probabilities? This ratio, the likelihood ratio, reflects the probative value of the footprint evidence, and it is the probative value of the evidence for the prosecution case. It is, on these assessed figures, approximately 1 : 4. That is the assumption I make when I say that the footprint evidence reduces the probability of David being guilty. The assumption may be far too generous to the prosecution, because the probability that David's foot could have left a print of the size discovered could well be much less that 0.25: in none of the tests did his foot leave a print of that size. There is a possibility that a stretched sock may move under the sole of the foot so that its heel is closer to the toes, and so produce a shorter blood print than the foot wearing it, and I assume that the people who carried out the tests were alert to this.

More relevantly to a civil standard of proof, for a probability of David's guilt of 0.49, thus qualifying him for compensation, and for all the other evidence in the case suggesting a probability of guilt of 0.95, the probability of his foot leaving a print of the size found would need to be 0.05. That is, out of every 100 footprints David made, 5 would be of the size found at the scene. Given that there is no scientific evidence that he ever left the size of footprints found, it should seem reasonable to allow that he might do so no more than 5 times in a hundred. In science, measurements are routinely considered acceptable if they are in the plus or minus 5% range, although obviously greater accuracy is preferred. To disqualify himself for compensation he would need to leave footprints of the size found at least 6 times in every hundred footprints.

The frightening thing about cases of circumstantial evidence (that is, like this case without the footprint evidence) is that an item of direct evidence proving innocence might be missing. We are very fortunate that in the investigation of this case the police did not trample all over the scene, that they noticed the footprints, that they had them measured, and that they disclosed those measurements to the defence. On the critical evidence there is no reason to criticise the police.

Nor should the defence be criticised for not noticing the significance of the footprint evidence at the first trial. We are very fortunate that Mike Guest, David’s then lawyer, introduced Joe Karam to David, and that Joe sensed that David was innocent. We are fortunate that Joe launched his campaign and wrote his books and persisted with David’s cause.

My conclusion is that because David can prove innocence beyond reasonable doubt he is entitled to compensation without the need to show that anyone acted improperly.

[Update: on 2 August 2016 a second and final report was published. At [115] its author, the Hon Ian Callinan QC (formerly of the High Court of Australia), states: "... the question is not whether the case could or could not accommodate the presence of Mr Robin Bain's footprints, but the reliability and probative value of the evidence of the footprints themselves in the light of all the evidence." If a criticism of this is to be made it would be that it could mean that the question of what the measurements were is determined by all the evidence in the case. Indeed, Mr Callinan appears to consider evidence other than that of footprint measurements as part of his evaluation of the evidence of their length, and says at [328] that the footprints are "inconclusive". In my opinion it is necessary first to determine what the evidence is, before turning to the question of its probative value. Mr Callinan does not demonstrate why the footprint evidence does not have the importance that it was acknowledged to have at the Privy Council hearing. He neglects to get to grips with what the evidence is: the objective evidence is the experimental results obtained by Drs Walsh and "Sandilands" [Binnie sic, Sandiford], see Binnie at [248]-[252]. The range of prints obtained from a 300mm foot would be 288-310 (Walsh) or 300-315 (Sandiford). And the range for a 270mm foot would be 258-280 (Walsh). None of the results gave a print shorter than the foot by 15mm which is what would be needed on all the assumptions favourable to the Crown and allowing a range of error for the measurement at the scene of plus or minus 5mm. The conclusion should have been that David was innocent, certainly on the balance of probabilities. It is easy to find support in the circumstantial evidence for any conclusion, but the footprints were direct evidence of who the killer was.]

Verdicts on appeal - and appeal verdicts - in Victoria

The interpretation of "substantial miscarriage of justice" in s 276(1)(b) of the Criminal Procedure Act 2009 [Vic] was the subject of Baini v The Queen [2012] HCA 59 (12 December 2012).

The decision will be of only limited interest where legislation differs, as for example it does in s 232 of the Criminal Procedure Act 2011 [NZ]. Here there is a definition of the required "miscarriage of justice", and what the appellate court needs to be satisfied of is that an error, irregularity or occurrence in relation to or affecting the trial has created a real risk that the outcome of the trial was affected.

But back to Baini, where the High Court of Australia split and two judgments were delivered. The majority, French CJ, Hayne, Crennan, Kiefel and Bell JJ, allowed the appeal and remitted the case to the Court of Appeal for it to determine whether, having regard to the whole of the evidence at trial, there could have been no reasonable doubt about the appellant's guilt.

Gageler J, dissenting, would have dismissed the appeal because the appellant had not shown that there was a reasonable possibility that the guilty verdicts would not have been returned if the error at trial had not occurred.

Those different conclusions reflect different interpretations of s 276(1)(b). The majority took a fresh start approach to the words of the enactment, whereas Gageler J read it in the context of the common law and its interpretation of common form appeal legislation. The difference between the judges was not merely in the application of s 276(1)(b), but in its meaning.

Central to the difference is the gritty problem of the extent to which appellate judges should act like jurors (see, for discussion, here, and links therein). Obviously in some appeals they have to, if it is submitted that a verdict was unreasonable. But here that was not the submission. When an appellate court is persuaded that an error at trial has given rise to a real possibility that a verdict was affected adversely to an appellant, should it thereupon quash the conviction or should it go on to look at the full record of the case and decide for itself whether the appellant was guilty?

Of course we are not considering different cases where an error at trial was sufficiently fundamental to make the trial unfair to the defendant. There is no doubt that if it did the court would quash the conviction. No, we are considering here lesser errors, but ones sufficient to give rise to a loss of a real chance of a more favourable outcome.

Whereas Gageler J found that the legislation changed the law so as to make the Weiss approach no longer appropriate in Victoria, the majority did not. Weiss, it will be recalled by the relatively few people who study this sort of thing, requires the appeal judges to in effect reach their own verdict. Although Gageler J thought that the legislative basis for Weiss had disappeared [46], [61], [67], the majority recognised that the new legislation left room for the Weiss approach by, as a matter of interpretation, including the inevitability of the verdict [15], [39].

The difference is between what the jury might have thought if the error had not occurred (Gageler J) and what the appeal judges think (majority) about the verdict despite the error.
I expect that our s 232 will be interpreted on its own terms without resort to the common law history concerning the method for deciding conviction appeals. The significant point is that the inquiry stops with a decision that an error (etc) has created a real risk that the outcome of a trial was affected, because that is all that this part of the definition of miscarriage of justice requires.

The unreasoned consequences of unreasonable search

Lawful powers must be exercised reasonably, and it must be reasonable to have resort to those powers. An illustration of unreasonable resort to lawful powers is R v Aucoin, 2012 SCC 66 (30 November 2012).

Upon apprehending the defendant for traffic offences involving licensing and alcohol the officer decided to detain him in the police vehicle because he was concerned that the defendant might run away. A pat-down search of the defendant was carried out prior to this detention. Cocaine was found in a quantity that subsequently supported the defendant's conviction for possession of cocaine for trafficking. There were alternative and reasonably available ways in which the officer could have addressed his concern about the defendant running away.

All members of the Court held that it was on the particular facts unreasonable for the officer to exercise his power to carry out the search and detention, but only a majority held that the evidence was admissible.

On the facts, backup was close at hand so there was no reasonable necessity to detain the defendant in the police vehicle. There was disagreement over the extent of the balancing required to determine reasonableness: the majority appear to accept that regardless of the seriousness of the offence for which the defendant was initially stopped, if detention was reasonably necessary to prevent flight there was no need to take account of the seriousness of the offence: Moldaver J for the majority at [43], disagreeing with LeBel J for the minority at [86].
It is useful when majority judgments directly address points made in minority judgments. Unfortunately such cross-referencing did not occur on the critical issue in the case: the admissibility of the improperly obtained evidence.

The majority addressed briefly the decision process required by R v Grant, 2009 SCC 32 (CanLII), 2009 SCC 32, [2009] 2 S.C.R. 353 (discussed by me here and here and here and here). It seems that the critical point of difference from the minority assessment is that the majority accepted that the officer was not simply applying his standard procedure for more serious offences when he detained the defendant [45], [48]. The minority view of the evidence contrasted sharply, referring to the constable's evidence about his standard practice in relation to detained motorists [101] and this, for the minority, was evidence of a pattern of abuse.

How do appellate judges arrive at such different assessments of the evidence?

All judges agreed that the defendant's expectation of privacy in relation to the contents of his pockets was high, but the minority mentioned too the aggravating feature of questioning the defendant about the contents of his pockets which introduced the right to be protected against self-incrimination [104]. This did not feature in the majority's analysis. Why not?

The majority said that the impact on the defendant's privacy rights was significant, but no more so than society's interest in having the case tried on the merits [51]. There is no explanation of how that evaluation was reached. Neither is there reasoned support in the minority judgment for its opposite conclusion on admissibility. What was the likely starting point for sentence for the cocaine offence (the defendant received a sentence of two years' imprisonment)? Probably it was not in the medium-to-high range, so how was society's interest measured? What relevant decisions supported the conclusion? What do other cases say about the defendant's privacy interests as against the seriousness of the detected offending?

Unpredictability comes from the vagaries of judicial assessment of the evidence and of the relative strengths of rights.