No police officers are to be prosecuted over the fatal shooting of Jean Charles de Menezes at a Tube station last July.
Jean Charles was an electrician working in London
But the Metropolitan force will be charged under health and safety laws.
The Crown Prosecution Service said there was "insufficient evidence" to prosecute any individual over the death at Stockwell, south London, on 22 July.
Alex Pereira, a cousin of Brazilian Mr Menezes, 27, who was shot seven times in the head, said the decision was "unbelievable" and "ridiculous".
"It's unbelievable what they sent to us today because we had to wait for a year and it was a hard year for us," Mr Pereira told a news conference.
Mr Menezes was shot by police officers after being mistaken for a suicide bomber.
Reacting to the CPS decision over health and safety, the Met Police said in a statement it was "concerned and clearly disappointed".
But on the decision not to prosecute individual officers it was "pleased for the officers and their families who have faced much uncertainty over the last year".
On 22 July 2005, a surveillance team had been monitoring a block of flats in Tulse Hill, south London, where Mr Menezes lived, in the belief that a man wanted in connection with the previous day's attempted suicide bombings in London resided there.
When Mr Menezes emerged from the flats, he was wrongly identified as the suspect and followed to Stockwell, where he was shot as he boarded a Tube train.
Senior CPS reviewing lawyer Stephen O'Doherty said the two officers who fired the fatal shots could not be prosecuted for murder or any related offences because they had "genuinely believed" he was a suicide bomber.
"The two officers who fired the fatal shots did so because they thought that Mr de Menezes had been identified to them as a suicide bomber and that, if they did not shoot him, he would blow up the train, killing many people."
Despite mistakes made in planning and communication by officers, there had been "insufficient evidence to provide a realistic prospect of conviction against any individual police officer".
The CPS said the office of Metropolitan Police Commissioner would be prosecuted under sections three and 33 of the 1974 Health and Safety at Work Act for "failing to provide for the health, safety and welfare" of Mr Menezes on 22 July.
An Independent Police Complaints Commission (IPCC) report, handed to the CPS in January but not yet made public, is said to be highly critical of the surveillance operation and police control room staff.
It is said to conclude that a series of organisational failings and communication difficulties had resulted in two experienced marksmen shooting dead an innocent man.
The IPCC said the question of potential disciplinary action against any individual officer would be considered under the Police Reform Act 2002 and its full report would be published as soon as "legal considerations" allowed.
Shami Chakrabarti, director of campaign group Liberty, said public confidence could not be restored until the IPCC report was in the public domain.
"I have to say that I think it's pretty unacceptable that we are now one year on and there's still no full rigorous account of what happened," she told BBC News.
A number of police officers were served with "regulation nine" notices and interviewed under caution by the IPCC.
They included Commander Cressida Dick, who was the designated senior officer responsible for the operation.
In its statement, the Met Police said Commander Dick and other officers whose actions were scrutinised "deserve our continued support at this time".
"We acknowledge and support today's decision by the CPS not to charge any officer with criminal offences for their part in the events of 22 July," it continued.
"However, we are concerned and clearly disappointed at today's decision to prosecute the Metropolitan Police Service for breaches of health and safety.
"Despite the uncertainty this prosecution will create we will not shrink from our key role of protecting public safety."