Maltese men who are aged between 16 and 35, and who are typically southern Mediterranean in appearance, would be well advised not to carry a rucksack when in London, not to wear a baseball cap, and under no circumstances must they wear a heavy coat or jacket, even if the British summer feels cool to them. If they can avoid travelling on the Tube altogether, then that would be so much the better.

Any spare cash spent on taxis might very well spare them from suspicion of terrorist activity. The Sunday Telegraph has published a list, based on formal advice, of what commuters on London buses and the underground should look out for when scanning the crowd of fellow travellers for potential bombers.

It reads like an identikit of a nervous young Maltese man, about to ask his dream girl for a date (“He will be licking his lips frequently and perspiring heavily …”) and wondering whether he has forgotten to pack his trainers for the gym after work (“If he is carrying a rucksack, he will be checking it often…”).

I sometimes think that, to anybody not bred in those parts of the world where dark-but-not-black people come from, all dark-but-not-black people are a mysterious mass of the racially undistinguishable. And right now, we are all under suspicion – or at least, the young men are. A ‘terrorist type’ has been described for the information of the British public, and unfortunately, that terrorist type can be found in the thousands on the Maltese university campus any day between December and April, when padded jackets are worn and rucksacks are carried.

Sometimes those padded jackets will even have the legend ‘New York City’ emblazoned across the front or back – a legend which, when seen on the jacket of a suspected Tube bomber, was thought to be a threatening reference to the catastrophe of 11 September, 2001. This is the kind of panicked inference that we can do without. It might have been the only jacket he owned. If it’s not New York on these jackets, it’s Los Angeles or Oxford or Harvard. I had a shirt with New York on the back when I was 12, and I wasn’t a bomber.

* * *

The ‘standard terrorist description’ overlooks the fact that the Syrian supposed mastermind who is being hunted high and low does not fit it in any way. He is a ruddy type with sandy hair, who would pass unnoticed downing a few pints of beer in a central European village, or a grappa in Milan. Nor does it account for the fact that the notorious ‘shoe bomber’ is English and looks it, despite the name he took on when he converted, fanatically, to Islam.

One of the bombers killed in the London blasts was born in Jamaica of Afro-Caribbean parents, and looked it. His wife, a fellow fanatical convert to Islam, looks English – at least, what can be seen of her beneath her encapsulating black shroud.

The vast majority of Maltese men of that age fit the ‘standard terrorist description’. Line up a collection of their passport photographs, and it will look like something that has emerged from one of Al Qaeda’s training camps.

This prejudicial assumption of what a terrorist looks like is one of the reasons that poor Jean Charles de Menenez, a 27-year-old Brazilian electrician of Spanish-Portuguese extraction, was shot in the head by police in London. The other reason is that he had the grave misfortune to live in a house divided into flats (as is often the case in London) that was under surveillance, because of suspected terrorist activity, by the police. The police said that they had not realised that it is a “multi-occupancy building”. So, when a man fitting the terrorist identikit walked out, and wearing a jacket, what’s more, he was followed, challenged, and then shot in the head when he tried to escape.

* * *

Why would a man who spoke perfect English, and who had a permit to work in Britain, where he had lived for the last three years, run away from the police when challenged? Why did he run when he had nothing to hide? The answer to that is perfectly obvious. The police officers were in plain clothes, and not in uniform.

When, in the streets of London, or anywhere else for that matter, you are set upon by several men brandishing guns, claiming to be policemen, you do not stick around to ask for proof of identity. You run. This is especially when you know that, famously, British policemen, unlike New York cops, are ordinarily unarmed and do not go in for the ‘stop or I’ll shoot’ scenario.

This young man was from Brazil. In Brazil, if a gang of armed men confronts you in the street, you do not enquire what their business might be. You run for your life.

If British police have been given instructions to shoot to kill ‘terrorist suspects’ – which might mean simply those who fit their idea of what a terrorist looks like, and who happen to be in the wrong place at the wrong time – if they try to run away when ordered to stop, then the police authorities had better ensure that only police officers in uniform may do this.

Confronted by a plain-clothes officer with a gun, how many of us would lean in close to examine his ID and work out whether it is authentic? It is safe to assume that most of us, when confronted by several heavily armed men in ordinary clothes, would do what Jean Charles de Menenez did. We would run.

Of course, this complicates things because policemen in uniform can’t very well hang around on surveillance duty without being noticed. But the presence of at least one uniform among them would have avoided this terrible thing.

* * *

When I heard on the BBC the description of how Jean Charles de Menenez was shot dead, I knew instantly that he was just somebody’s innocent son, from one of the warmer parts of the world, studying or working in London. I thought to myself that some family in Italy, Malta, Spain, Greece, Turkey, Egypt or similar was about to be smashed apart by grief.

It’s already devastating to receive the news that your son has died in a car crash, or some other commonplace horror. How can we even begin to comprehend what Matuzinho Otone, the father of the young man, is going through now, trying to imagine the last minutes of his petrified son’s life, and how he was killed by police shots to the head, on the floor of a crowded underground train carriage?

It is precisely the sort of thing that might happen in Brazil. He probably never imagined that it would happen to his beloved son in civilised London. Mr Otone’s face, in the press photographs, is a picture of Biblical grief and suffering. The last time I saw that expression, it was on the face of a painting of Our Lady of Sorrows.

So how did I know immediately that the police had shot the wrong man? I can’t work it out, but there was something in the way that the interviewed bystander described it to the BBC. His shocked, spontaneous words indicated that what he had seen – and consequently described – was a terrified and bewildered man running for his life, rather than a guilty one trying to evade the police. We communicate and pick up meaning in subtleties of language and behaviour without even being aware that we are doing so. In this case, with me, it was the man’s use of the words “he was like a petrified fox; he was terrified”.

There was something else too. In all the news reports I have read of suicide bombers who are challenged by policemen or soldiers, there is a salient fact. Their immediate reaction when apprehended is to try and detonate the bomb. They try to escape captivity not by running, but by blowing themselves up.

The police shot Jean Charles de Menenez because they thought he was a suicide bomber with explosives packed beneath his jacket (he wasn’t carrying a rucksack). Yet nothing in his behaviour indicated that he was a suicide bomber, rather than a terrified young man chased by what he must have thought was an armed gang.

* * *

This was a dreadful case of jumping to conclusions. From these bare facts – a Latino man in his 20s, wearing a jacket in what the British consider to be warm weather, coming out of a house divided into flats where others might have been up to ‘terrorist activity’, running away when they challenged him – the panicked police concluded that he was a suicide bomber. They chased him and shot him dead. I wouldn’t like to be the policeman who killed him. If he is a decent man, a lifetime will not be enough for him to recover from the fact of what he has done, the innocent young life he has ended, and the bottomless grief he has caused.

The Metropolitan Police Commissioner, Sir Ian Blair, said: “This is a tragedy. The Metropolitan Police accepts full responsibility for this. To the family, I can only express my deep regrets.” Somehow, that seems terribly inadequate, as though the police had run over somebody’s dog by mistake. How would you feel if, last Friday, you were the one to receive the news that the ‘suspected suicide bomber’ shot by the police on the London underground was your son or brother, who was in London on holiday, to study or to work? It might very well have been, given that there are so many Maltese men of that age and physical description in London, who would sensibly run from anyone chasing them with a gun. That’s how haphazard and horrible this killing was: it could just as easily have been 22-year-old Joseph Zammit from St Julian’s, wearing warm clothes like his mother told him to do.

* * *

I hope the family of Jean Charles de Menenez finds the time, money and inclination to hit the Metropolitan Police with a massive law suit. It won’t bring the young man back, but it needs to be done. There can be no justification for this killing, and no explanations that wash. His death was the result of a lethal combination of panic and prejudicial stereotyping. Would a young man who fitted the ‘standard British tourist description’ (our own version of this kind of stereotyping) have triggered the red alert system in the minds of the police who were watching outside that doorway? Somehow, I doubt it.