I was recently stopped by ISP while using a bypass through Gary due to I65 being closed. The officer approached the passenger side of the car and while I was fumbling around to get the button unlocked so I could lower the passenger side window he opened the passenger side door which I must have mistakenly unlocked while fumbling with the window controls. I was looking down to the left at the controls and having difficulty seeing them in the dark and was very startled when the door opened. Ive never had a officer try to open my car door before, is this a normal procedure and something they are allowed to do?