You might think so, but if Canadian law is similar to what is described for US law in Wikipedia,
"It is now possible to be convicted as an accessory before the fact even though the principal has not been convicted or (in most jurisdictions) even if the principal was acquitted at an earlier trial."
http://en.wikipedia.org/wiki/Accessory_(legal_term)
Section 23 of the Canadian Criminal Code
23. (1) An accessory after the fact to an offence is one who, knowing that a person has been a party to the offence, receives, comforts or assists that person for the purpose of enabling that person to escape.
But then there's this somewhat puzzling addition in Section 23.1
"For greater certainty, sections 21 to 23 apply in respect of an accused notwithstanding the fact that the person whom the accused aids or abets, counsels or procures or receives, comforts or assists cannot be convicted of the offence."
There's an interesting discussion about this controversial subject at a legal blog. I'm not sure if the rules permit posting the link. Generally, the effort is to determine what would be considered aiding and abetting a person if that person is not convicted. Examples are provided such as crimes committed by children statute barred from conviction because of their age. They also describe a very controversial case which bears similarities to this one. In 1975 a guy named Vinette was charged with helping Vincent dispose of a body after the fact (obviously.) Vincent eventual pled guilty to manslaughter and that "confession" was given as evidence to convict Vinette. Debate raged around the question of whether a person could knowingly provide assistance to a person "after the fact" if the crime had not yet been committed. Much more recently, in 2014, in the Huard accessory case, the Supreme Court of Canada upheld a ruling that allowed the accessory to be convicted of a more serious offense than the main offender. Mr Huard was convicted as a party to a first degree murder even though the main offender's charge was reduced to second degree murder.