@John121 I take it you were with him at the time? In these circumstances you should always take the collar number of the police officers at the scene, but if you didn't then you'll just have to try and get information out of the police. I wouldn't bet on them giving you a response within a useful timeframe, but you should try nonetheless.
In the meantime this is a reasonably straightforward representation:
Dear London Borough of Newham,
I accept I drove through the no entry signs, but this is because I was directed to do so by a police constable in uniform. At the material time the police had cordoned off Rixsen Road (just before the Berkeley Road junction) due to an incident where someone was apparently attempting to commit suicide by jumping off a building. As a result there was no other way out, and the police directed me to go through the no entry restriction as there was no other way out. I was not the only one; several other vehicles were also directed to do the same and I'm sure your records will reflect this. As I am sure you will appreciate, failure to comply with the direction of a police constable in uniform is a criminal offence.
I attach several photos taken at the time showing that the police had cordoned off Rixsen Road.
Yours faithfully,
Send this online and keep a screenshot of the confirmation page.
@Southpaw82 @andy_foster I know there's some case law about police officers being empowered to direct motorists to contravene section 36 signs such as traffic lights etc, do you guys happen to have a reference?