The prosecution has to prove guilt; does it also have to prove its evidence is admissible?

One would have thought, prior to R v P 11/6/04, CA102/04, that if the defence advanced grounds for disputing the admissibility of prosecution evidence, then the prosecution would have to satisfy the court that its evidence was indeed admissible. The party adducing evidence should have to establish that such evidence is admissible. The same applies, one would have thought, to defence evidence: if the prosecution advances proper grounds for objecting to its admission, the defence should have to establish the admissibility of the evidence it proposes to use.
Not so, we now are told in P. The court likened the pre-trial procedure for obtaining rulings on admissibility under s 344A of the Crimes Act 1961, to civil proceedings to review a determination on the issue. The result should be the same, said the Court, as far as the burden of establishing the issue is concerned. Therefore, said the Court, under s 344A the defence must satisfy the judge that the evidence is not admissible.
The likening of the two kinds of proceedings is fallacious. The wording of s 344A is such that it requires the party seeking to adduce the evidence (usually, but not necessarily, the Crown) to obtain an order that its evidence is admissible. The court needs to be satisfied that the evidence is admissible before it can make the order. By contrast, in civil proceedings for review of an order admitting evidence, the party objecting to admission of the evidence (usually - not that this form of procedure is often used, for obvious reasons - the accused) has the burden of persuading the court that the order of the court below was erroneous. The party with the burden is different, according to which form of procedure is used.
It is unlikely that s 344A was introduced in order to put the burden of persuading the court on the accused, contrary to the plain meaning of its words.
The better view, it is respectfully suggested, is that of the Privy Council in Mohammed v The State [1999] 2 AC 111, holding that when there is an issue of breach of rights, the prosecution has to prove beyond reasonable doubt that there was no breach. If it cannot do so, and if the issue is the fairness of the trial, then the evidence cannot be admitted; but if the issue is compliance with some other, non-absolute right, then a balancing exercise is required. Only in the latter case, where balancing occurs, are the notions of burden and standard of proof on the issue of admissibility inappropriate. That point is only reached, however, after the prosecution has been unable to exclude a reasonable possibility that a breach of rights occurred.