The common law doctrine of joint enterprise allows for the conviction of ‘secondary parties’ to a crime committed by another, ‘principal’ offender. It can afford the courts a proper degree of subtlety: the getaway driver can be answerable for the bank robbery, not just a parking ticket. It’s a blunter instrument when the collective nature of the offence is less clear. Researchers at Manchester Metropolitan University recently published a report into the criminalisation of women convicted under joint enterprise.