The family of the Brazilian man killed by police said he had acted as "training" for the security forces.
They said that by shooting dead 27-year-old Jean Charles de Menezes the police had learned the wrong course of action - and were now using stun guns instead.
Mr Menezes was gunned down last Friday as he fled from police at Stockwell Tube station in south London.
He was shot eight times - seven bullets direct to the head - after police followed him from Tulse Hill in south London.
Four of Mr de Menezes's cousins spoke out on his behalf yesterday at a joint press conference in north London before flying his body home.
Alex Pereira, aged 27, said his cousin's death had given police a lesson they needed.
Mr Pereira said: "They learned, it means that my cousin was training.
"They killed one person to learn that lesson, I hope they never kill again." The family insisted that Mr Menezes did not jump the barrier at the Underground station, nor was he wearing a heavy jacket as was reported at the time.
Vivien Figueiredo, aged 22, said police told her he was wearing a jean jacket and had used his travel card to get through the station.
She said he had done nothing wrong when he was killed.
Ms Figueiredo expressed anger at reports that one of the officers involved in the shooting had gone on holiday, paid for by the Metropolitan Police.
Speaking through a translator, she said: "It is not right that this person should now be enjoying his holiday when we are suffering.
"We want to know what happened to this person, we want to see pictures of this person.
"He should not be on holiday at the moment, he should be incarcerated."
Mr Pereira added: "You have to make sure you bring him back and put him in the right place and show the world he did something wrong."
All four members of Mr Menezes's extended family called for the banning of the shoot-to-kill policy and said the war on terror must be fought with peace.
Ms Figueiredo said: "I understand they need to combat crime but they should not combat crime with crime.
"They should not be exterminating people unjustly which is what happened to my cousin Jean."
She described the 27-yearold electrician as a "extremely honest" person who lived life to the full and never strayed.
Patricia Da Silva Armani, 31, stressed that their cousin had always lived within the law.
She went onto stress: "I want to make it very clear about his status.
"He was legal in this country and he was allowed to work and study."