Wolfgang, almost every post on this thread concerning this incident is hindight and speculation including yours. However, checking out a person of suspicion is done in this country all the time and is generally considered the logical action of a prudent police force.

Here such action is standard regarding the possession of drugs/alcohol/stolen property or surprize! even concealed weaponsand sometimes, unfortunately, as in the UK, conducted just as an excuse for harassment based upon the racial or ethnic prejudice of individual officers.

According to Mr.de Menezes' cousin, this practice is or was standard in Britain too. Mr. de Menezes had been checked out by police in the past for lesser concerns than possibly carrying a bomb. All police searches carry an element of risk to the officers involved, even for a pocket full of marijuana, but, it is their job, even when things get very tough indeed.   

A little game of I Spy and put a few bullets in his head if things get too dicey in a crowd? Get real Wolfgang, one expects competence from a professional police force, even more so during a time of crisis. This is not a computer game or movie fer gawds sake and the public has the right to expect the police not to deliberately put them in harms way.