A person attempting to commit an offence can be criminally liable for the attempt. For any attempt to be made out, the person's actions must be more than "mere preparation":
24. (1) Every one who, having an intent to commit an offence, does or omits to do anything for the purpose of carrying out the intention is guilty of an attempt to commit the offence whether or not it was possible under the circumstances to commit the offence.
Question of law
(2) The question whether an act or omission by a person who has an intent to commit an offence is or is not mere preparation to commit the offence, and too remote to constitute an attempt to commit the offence, is a question of law.
R.S., c. C-34, s. 24.
There is no general criterion to distinguish between mere preparation and actual attempt.
There is however a "qualitative" distinction that can be made:
- "...the distinction between preparation and attempt is essentially a qualitative one, involving the relationship between the nature and quality of the act in question and the nature of the complete offence, although consideration must necessarily be given, in making that qualitative distinction, to the relative proximity of the act in question to what would have been the completed offence, in terms of time, location and acts under the control of the accused remaining to be accomplished. I find that view to be compatible with what has been said about the actus reus of attempt in this Court and in other Canadian decisions that should be treated as authoritative on this question."
The trial judge should consider the "relative proximity of that conduct to the conduct required to amount to the completed substantive offence. Relevant factors would include time, location and acts under the control of the accused yet to be accomplished.”
- R. v. Sarrazin,  O.J. No. 3748 (C.A.), at para 54
- R. v. Root 2008 ONCA 869, (2008), 241 C.C.C. (3d) 125 (“authorities have yet to develop a satisfactory general criterion to assist trial judges in making the crucial distinction between mere preparation, on the one hand, and an attempt on the other.”)
R. v. Deutsch, 1986 CanLII 21 (SCC) ("the application of this distinction to the facts of a particular case must be left to common sense judgment.")
- R. v. Deutsch, 1986 CanLII 21 at 27
- R v Root, 2008 ONCA 869