I don't see this as a screw-up.
Men with bombs are blowing up train stations and killing people.
A man in heavy coat in summer comes out of a building under surveillance for terrorism.
When told to stop, he runs into train station.
He jumps the turnstyle and heads into a trian.
Is there any other logical outcome other than he turns out to have a bomb and kills lots of people?
The officers did exactly the right thing.
The death was unfortunate, but there was no reasonable alternative for the police.
You said it.
Not to pour salt on the wounds of the cousin who's constantly in the press about it, who can't seem to understand...how about we check and see if they're legal while we're at it.
Did they ever explain why the victim was in the building that was under surveillance?
Well, yes, there was another logical outcome.