basic-rider

UK prison slang for an inmate who doesn't care if he breaks the rules in prison, he (it's usually a he) won't take drugs tests and gives the screws a hard time and gets a hard time in return.

Conversation on the wing: "See Joe over there, strutting round like he owns the place, he doesn't give a crap."
"Yeh."
"He's a basic-rider."
"Knob."
"Yeh. I want to do my time and get out of this shit-hole."