Photograph of the entrance to the Police Station in Church Road, showing details above the door. c1944 
Picture Stockton Archive
A Pictorial History of Stockton-on-Tees
Photograph of the entrance to the Police Station in Church Road, showing details above the door. c1944
Not sure about the part about blocking light from the doorways. Light would easily have been seen blazing from the top of the doors ..especially from the air.
The breeze type blocks outside the main doorway of the Police Station were erected during the war as a defence against bomb blast and to prevent light showing on to the street when the doors were opened during the hours of darkness.