If legislation  has omitted to provide for an offence of procuring a controlled drug for supply, and so also omitted an offence of attempting  to procure the drug for supply, can there be implied into the legislation an offence of attempting to have possession of a controlled drug for supply?
This was a puzzle that intrigued subtle-minded law students when I was at law school.
It raises questions about the interpretation of criminal legislation: should the narrow view be taken, so that it is for the legislature to plug the gaps if that is what it wants to do, or should the courts fill in the gaps on behalf of the legislature under the guise of applying what is thought to be the legislature’s intention?
There could be good reasons for the omission from the legislation of an offence of attempting to have possession for supply. For example, possession for supply is a state of affairs, of itself causing no harm to anyone. It doesn’t make a drug available to potential users (that is addressed by the offences of importing, manufacturing, cultivating, supplying). The offence of possession of a drug was introduced relatively late in the history of our drug laws.  It is a sort of preparatory (inchoate) offence. Of itself, it is less of a threat to the community than conspiracy to supply a drug, or attempting to procure a drug. Those offences will usually involve interaction with other people, and it is their combined interest in the drug that is the threat to the community. A person who has possession of a drug for supply could be said to be on the threshold of committing a more serious offence. There might follow an attempt to supply the drug. The possession might be part of, or might lead to, a conspiracy to supply the drug. No one doubts that there are such offences as attempting to supply a controlled drug and conspiracy to supply a drug. The law extends plenty of community protection in such circumstances. And the offence of attempting to procure the drug is available too, but the penalty is (deliberately, in view of the reduced societal threat) lower. 
On the other hand, perhaps it is so obvious that there is an offence of attempting to have possession of a drug that there was no need for the legislature to say so. Possession is an offence, and an offence can be attempted.  The ingredients of the offence are: having an intent to have possession of the drug, and doing or omitting an act for the purpose of achieving that possession, as long as that act or omission is not merely preparatory for the commission of the possession. This is really the same as attempting to procure the drug, but there is no offence of procuring a drug for supply and therefore no offence of attempting to procure a drug for supply. So, on this interpretation, an offence of attempting to have possession of a drug for supply does the same work.
Strict interpretation, or purposive interpretation? Which shall it be?
The history of this issue, and its present resolution, is addressed in Mesman v R  NZCA 418 (7 September 2022).
The phrase that sticks out for me, probably because it must have been written with a twinkle in the eye, is in para : “Statutes … have never been a safe haven for the grammarian …”. Of course this is not to be taken literally, because grammar is of fundamental importance in statutory interpretation. But it flags a pragmatic approach in the service of harm reduction.
The appellant had tried to obtain delivery to herself of a package by courier (-). My knowledge of this case comes entirely from the judgment, but it seems to me that the appellant may have been liable as a party to the attempted supply of the drug to herself by inciting that attempt. 
The Court in Mesman held that there is an offence of attempting to have possession of a controlled drug. Noting at  that the Crimes Act “criminalises attempts to commit any offence”, the Court begged the question. The Crimes Act does not criminalise attempts to commit “any” offence, but uses the word “an”, which can mean “an offence that can be attempted”. A ruder person that I could think that judgments have never been a safe haven for logicians. And of course they haven’t, for policy has its place and may well override logic in matters of statutory interpretation.
 The legislation relevant here is s 6 of New Zealand’s Misuse of Drugs Act 1975.
 Our relevant attempt offences are provided for by s 72 of the Crimes Act 1961.
 The first of our drug possession offences was introduced in 1908 and referred to opium that had been imported in contravention of customs legislation. The first drugs legislation was the Sale of Poisons Act 1866 and this was directed at the labelling of containers of poisons which included opium and laudanum. Then, in 1871 an upgraded Act required vendors of poisons to be registered.
 Procuring is an offence against s 7(1)(a) of the Misuse of Drugs Act 1975, and the attempt is an offence against s 72 of the Crimes Act 1961, with the penalty provided for in s 311 of that Act (a maximum of half the penalty for the full offence).
 But “an” is not necessarily “any”. If it were, there would be an infinite series of attempts to attempt.
 Party liability is governed by s 66 of the Crimes Act 1961. By consigning the drug to the courier, the supplier did everything necessary to commit the attempt to supply the drug to the appellant. By inviting that attempt, the appellant appears to be liable for the incitement. There is some conflict of authority on whether the supply must have been intended for someone else (the offence is “supply to any other person”, s 6(1)(c)), but it seems sensible to say that the other person is the appellant. This is the approach taken in R v Drew  1 Cr App R 91,  Crim LR 581 (CA).