I had a situation where I had someone stopped. (ALPRS [or whatever its called]) detected an expired registration. When I went up to the window there were two occupants, I ran their names, and the passenger came up wanted. I called for assistance since there were two, and I didn't know what was going to happen... All of a sudden here comes my backup wailing and screeching through the street only to cause a bigger scene.. I was wondering if there was a way to make them show up without sirens, and maybe just stop before they pass my car?

Simple answer, no.

Simple answer, no.

haha okay thank you

You can use API and make a custom script to do it.

Well actually I was going to a call with siren off, and set a waypoint and called backup there. They appeared also siren off. 

Guess ill do some fiddling around, and Hastings maybe they show up as you are presenting yourself, I'll give it another shot.