Parties to Crime and Inchoate Offences

The correct answer is B. Section 4(1) of the Criminal Law Act 1967 provides that where a person has committed a relevant offence, any other person who, knowing or believing him to be guilty of that or some other relevant offence, does without lawful authority or reasonable excuse any act with intent to impede his apprehension or prosecution is guilty of an offence. A stabbing is a relevant offence — one for which the sentence is fixed by law, or which carries five years or more for an adult with no previous convictions (s.4(1A)). He believed his flatmate guilty of it, and washing the shirt, scrubbing the knife and driving him out of town were all acts done with intent to impede his apprehension.

Note that the old category of "accessory after the fact" no longer exists. It belonged to the law of felony, abolished by s.1 of the Criminal Law Act 1967, and ss.1 to 7 of the Accessories and Abettors Act 1861 were repealed at the same time. Sentence is graduated by s.4(3) according to the offence assisted, and proceedings may be brought only with the consent of the Director of Public Prosecutions (s.4(4)).

A is incorrect because s.8 of the 1861 Act reaches only those who participate in committing the offence; help given once it is complete is not participation, so he is not punished as a principal. C is incorrect because assistance given after the offence is precisely what s.4(1) criminalises. D is incorrect because although perverting the course of justice could also be charged, these acts fall squarely within s.4(1); the offences overlap rather than exclude one another. E is incorrect because s.4(1) requires only that D knows or believes the offender to be guilty; witnessing the offence is not required.