- how to catch a crack head and send them to jail: seriously. this is not hard. sure, being a crackhead, per se, is not a crime. you can't get someone sent to jail just for being a crackhead. however, if the person you're thinking of is actually a crack smoking crackhead [as opposed to someone generally stupid who you're calling a crackhead-as-in-numbskull], your best bet is to call the police and tell them that the crackhead has crack. the local constabulary will be more than happy to act on your tip and take credit for removing another crackhead from the streets of their virtuous town.
- how do you know if you have a crack head on your car?: first, we'll assume that you know that the thing on your car is, in fact, a human being--if you can't figure that out, you're beyond help. the method to use to figure out whether the person on your car is a crackhead or not depends on whether the person is dead or alive. if he is dead, call the cops. the cops will take him in, the coroner will do an autopsy, and the toxicology report should tell you whether he is a crackhead or not. if he is alive, ask him if he wants some crack. if he says yes, he's a crackhead.1 if he says no, he's probably not a crackhead.
1 yes, i know. the astute ones among you are probably thinking that it's a bad idea to ask a crackhead if he wants some crack if you have no crack to give him. it's definitely a risky thing to do, since the crackhead will think you have crack and may get angry at you for not giving him any. but, this is slightly less dangerous than the other alternatives for finding out whether he is a crackhead, such as rifling through his pockets or drawing blood for a drug test. if you do anything that requires contact, he may try to punch, kick, or cut you. at least you can ask him if he wants crack from a slightly safe distance...and get a head start on running away from him if he starts to break into hot, crackheaded pursuit.