In LCPDFR 0.91, other police officers and I arrested a man, the man got into my car, and I drove him to police station, then what should I do?

You have to drive your car into the red marker.

But there is no red marker outside or near to the police station!

Make sure you've arrested him and clicked "Drive to nearest police station"

If you have and you still don't have a red marker, press CTRL+DEL to start debugging.

Once its done, the last resort (if it still ain't working) is to open the console by pressing ~ and type 'reloadscripts' (No quotations)

If that STILL fails, make a Diagnostics report and post it here

When you say you and other officers arrest a man, if he/she gets in the car based on the other officers orders, there not much you can do, as you did not actually initiate the arrest system. I've has this happen to me before. One night I almost had a guy in my back seat all night. The funny part though when I did arrest someone, they threw the other guy out as they got in. I could be wrong, but I have a feeling this could be the case here.