Is it legal for a police officer to sit in his patrol car in a private driveway and point his radar gun at passing traffic.

The speed limit is 25 miles an hour on this road and they occasionally sit on a side road and catch speeders. The last few days he has been sitting in his marked patrol car in a driveway of a house. He is backed up right to the garage next to the residents two cars. The driveway is about 50 feet in depth. He is pointing his radar gun and stopping people who are speeding.

Is it lawful for him to sit and perform his duties from a private driveway?