Police can do anything they want to you at anytime. Stop you, hit you, remove any valuables from you, have sex with you, no limits. If it isn't mentioned in statute then it is the same as so by non-enforcement by each other and if a video gets made of the incident then the prosecutors and judges will do their best to get the officer clear.
"My message to my troops is if you see anybody carrying a gun on the streets of Milwaukee, we'll put them on the ground, take the gun away and then decide whether you have a right to carry it." - Milwaukee Police Chief Ed Flynn
