Some cops are just on a power trip and harrass people because they can. When my husband was younger he got pulled over for no good reason. The only thing the cop would say was he thought he saw a weapon. He asked my husband if he had any weapons in the car and he answered truthfully that yes he had a compund bow locked in the trunk because he had been hunting that morning, but there were no firearms. He showed his hunting license.They asked to search his car and he refused. He ended up handcuffed on the side of the road for 3 hours with multiple cops and eventually the supervisor there all because of a non existent handgun.
He finally allowed them to search one part of the car at a time with the agreement that he was there watching so they didn't plant anything. They ripped his car apart. When they popped the trunk open, there was the hunting bow just as promised, but no handgun. They were obviously pissed off as my husband started laughing at them for wasting 3 hours of their time for nothing. He got the cops name and badge number and reported it to his cousin on whose property he had been hunting who was an officer for a different agency, but managed to get the cop reprimanded.
Cops just like to harass young people to intimidate them and to look for easy tickets and arrests so they can get promotions. They tend to go much harder on boys than girls though. I've never been harassed and any time I get pulled over for speeding, I pull the keys out of the ignition and throw them on the dash so they know I won't flee,
keep my hands in plain view, tell them I need to reach into the glovebox to get my registration so they know I'm not reaching for a gun and smile politely. And if they ask if I know why I've been pulled over, I just say no and when they inform me, don't make any admissions of guilt. I've never had a problem and a few times I've only got a warning!