Argus alluded earlier to the idea that only those involved in a criminal enterprise ("criminal organization" in official terms) need to worry about the law, referencing the example of a friendly poker game. But how is a criminal organization defined?
The Criminal Code includes numerous provisions dealing specifically with organized crime. Section 467.1(1) of the Criminal Code defines “criminal organization” to mean a group, however organized, that
(a) is composed of three or more persons in or outside Canada; and
( has as one of its main purposes or main activities the facilitation or commission of one or more serious offences that, if committed, would likely result in the direct or indirect receipt of a material benefit, including a financial benefit, by the group or by any of the persons who constitute the group.
So persons A and B each throw in $10 and approach person C to buy a quantity of marijuana less than 3 kg with their combined money. The (temporary) association of all three people would appear to exist for the main purpose of completing this transaction, which offers a financial benefit for person C and material benefits for the other two. In the case of a poker game between at least three people, it would not be impossible to make a similar argument, although personally I don't believe enforcement is very likely in that case.