Music such as street and punk rock can have a negative effect on people's behaviour because of the language used in them. Children are easily influenced by what they hear and their surroundings. Certain songs can change children's behaviour, which can change their futures for the worse. Ruining their futures.
Ok first of all does watching a violent tv show or movie such as Dexter or the movie Carrie make someone want to kill someone? Its the same for movies just because you listen to really heavy metal that screams KILL over and over again doesn't mean you will go on a violent rampage.
Music cannot be considered responsible for people's behavior, otherwise you would be able to draw some sort of direct line connecting heinous acts with certain genres, which we cannot definitively do. Music does not dictate what we do. You don't listen to ICP and suddenly feel the uncontrollable urge to kill a preacher. You don't listen to NWA and then go shoot cops. However, it is reasonable to suggest that music affects our mood, at least as much as any other aspect of our settings. Listening to darker sounding music may intensify negative feelings, while listening to positivity may boost positivity. Music affects your mood, not your actions.