No because there is not a lot of circumstances when cops are sitting in the same room with criminals while those criminals commit crimes to witness the crimes themselves.. Instead they get information from any number of sources that one or more crimes may have been committed., and they investigate that information and find out if that information is credible and they follow the facts, and the law and the witness statements and the evidence by further investigating. Cops are of a far more limited supply than crimes and criminals are. I am dismissing this conversation now because its not up to my standards. I don't normally have to spend a lot of time explaining why our system of law enforcement requires police investigations of criminal charges before they file charges in an indictment. Kids are pretty good at catching on to this concept at a pretty young age.