What type of criminal was Crisp?

Porn star

Its stated in the beginning of the film, when Kimble is chasing him around the mall, that Crisp is the head of an underground chipmunk fighting ring.

I've seen things you people wouldn't believe

He was caught at 16 smoking a joint in the privacy of his own home. Over-zealous prosecutors and judges who wanted to be "tough on crime" gave him to two years in state prison. Due to this, he was unable to graduate high school with his class and was forced to try to find employment with no skills when he got out. Due to his criminal record and lack of job skills, no colleges would accept him, despite being a straight A student before being sentenced. Unable to find employment, he turned to selling weed to make money and eventually moved up to coke and heroin. Naturally, he was caught again and sentenced to a longer prison term. This pattern simply repeated up to the time of the movie. John Kimball was the one who first busted him for the joint when he was only 16 years old.

'Murga.

Watch me whip.

It is said by Kimble at the beginning that he was a drug dealer. The scene where they're in the station and he says his wife stole the drug money he had earned and ran off with it. Though later that turns out to false but with that line we know he is a drug dealer.

"I'll be back!" The Terminator