It was a terrible decision for the police involved and it will live with them for ages.
He could have been wired to explode and they would have risked the lives of many around them had they not taken action. Yet again he may not have understood who was chasing him and why? (He had been in the UK for 3 years so you would hope he would understand English!).
I don’t think you can label this as any thing other than a very unfortunate accident. The press cannot be allowed to use this to drive a wedge between the police and the public. If we allow this wedge to increase, the bombers will succeed. Let us educate the public that if challenged, STOP. Do not leave unattended items, do cooperate at all times.
We must help the police and authorities in this problem and not put them in the position that they were placed in this unfortunate instance. My heart goes out to both the family and friends of Jean Charles de Menezes and to the officers involved.
As to whether the police have a shoot to kill policy, the press need to rename this as Shoot to Save Lives.