As we know, powers under the Town and Country Planning (Control of Advertisements) (England) Regulations 2007 may be exercised only in the interests of amenity and public safety.
In the old days, when we were safe and life was simple, public safety considerations nearly always related to whether an advertisement would prove to be a distraction to motorists. Following recent violent incidents in London and elsewhere it seems that we live in a different world now.
In (DCS Number 400-015-126) an inspector granted consent for a double-sided digital screen forming the end panel of a bus shelter in north London. With regard to amenity, he found that the character of the street scene was vibrant and busy and he considered that the advertisement would not appear incongruous in its busy urban setting. What marks out this case as notable is that in the event of an emergency, Transport for London will be able to override the advertisement function and display an emergency message, alerting the public of immediate danger.
How times have changed.
The following DCP chapter is relevant: 30.033