... talking to the person in the passenger seat ..
When I worked near Buck Place I saw some old biddie driving along The Mall busy chatting to her passenger just as if they were neighbours gossiping over the fence while hanging out washing. She sailed straight past the cop on point duty despite his raised hand - and despite also, when he saw what she was (not) doing, a loud whistle and a "STOP!". She was blissfully ignorant of the entire episode.
The cop turned his head around just long enough to clock her number.
I doubt whether Gladys was taking Vera on joyrides through London for much longer after that.