No there isn't.
No
you cant
You can't, its a mod.
go to the clorth shop
You can't.
Walk through the door
Look on one of the billboards on free mode and it will give u a number to call the police department and will automatically become a police officer
get a cop car and park and hit right bumper
You can't. You can be a good bystander though!
Because your a bad guy you can't become a cop on gta 4 unless your a good guy.And you got to do missions or you fail.Thats why it's called Grand THIEF auto get it
steal it from the nypd/new york police department on gta 4