The USA has about 88,000 jurisdictions, federal, state, and local. They each make up their own rules, regulations, ordinances and laws, and they each enforce them differently.

Many of the laws are unconstitutional and would be overturned by an honest court. Unfortunately, most judges were former prosecutors and have a vested interest in the system.

The Constitution and its Bill of Rights are technically the supreme law of the land, yet without infinite time and money, justice is rarely served. There's no right to search without probable cause, unless you give permission. If a cop asks you to turn out your pockets and you comply, they consider this permission. If you refuse, then you're escalating the situation. Talk to an attorney or civil liberties groups for better info. Sorry, the USA is not the country that it used to be.