Officers involved in the fatal shooting of Jean Charles de Menezes on the Tube could face charges, it has emerged.
Mr Menezes was shot dead at Stockwell Tube station
The Independent Police Complaints Commission (IPCC) said it was "likely" to send its report to the Crown Prosecution Service to consider.
The IPCC did not quiz Met Police chief Sir Ian Blair in person for its report. The Tories branded this "inexplicable".
Mr Menezes, from Brazil, was shot dead in Stockwell in July after officers mistook him for a suicide bomb suspect.
IPCC chairman Nick Hardwick said its investigation had to decide whether its findings indicated that criminal offences may have taken place.
This was a lower threshold than for the CPS, which would then have to decide whether to bring actual charges against any of the officers involved, he said.
Mr Hardwick said it was "likely" but not definite that the report would be sent to the CPS to consider bringing charges.
"It's for the CPS to decide, not us whether there are criminal charges to be brought against anybody and if so what they are," he said.
The IPCC's director of legal services John Tate said that if the report was sent to the CPS, it would include a list of the criminal offences which may have been committed.
The IPCC would not detail the nature of the alleged offences which the CPS could potentially have to consider, although it is believed they could include offences as serious as murder or manslaughter.
A spokesman for the Menezes family campaign said it was "dismayed" that the IPCC had held a media briefing.
"We have supported the IPCC and the family have always accepted that the IPCC investigation would remain confidential," the spokesman said.
"It is therefore very alarming that the IPCC have inexplicably released partial information in this manner to the media."
Mr Hardwick said they had interviewed a number of Metropolitan police officers of all ranks over the fatal shooting of Mr Menezes, but police commissioner Sir Ian Blair was not among them.
The Conservatives criticised the decision not to interview him as "inexplicable".
"The public expect no stone to be left unturned in this inquiry," said Shadow Home Secretary David Davis.
"The last thing anyone wants is to encourage conspiracy theories about a cover-up."
The inquiry would not confirm whether it had received a written statement from Sir Ian.
A separate IPCC inquiry is being held into his handling of the affair.
This was announced last week, after the Menezes family lodged an official complaint alleging that he and other senior officers made false public statements following the shooting.
Mr Hardwick said they had spoken to everyone they needed to for the inquiry into the shooting itself and were confident they knew what happened at Stockwell Tube station and why.
"We are confident we know, second by second, what happened on that train," he said.
Questioned about reports that some of the CCTV tapes from the Tube station platform may have been missing, Mr Hardwick said: "We are comfortable that we have all the tapes that exist. We have always said the tapes are significant."
Senior investigator John Cummins admitted there had been "problems" with the equipment, but did not elaborate further.
All 30 passengers in the train carriage at the time of the shooting had also been interviewed, Mr Hardwick added.
In total the investigation took 600 written statements.
Mr Menezes, 27, was shot seven times in the head by anti-terror officers after being mistaken for a suicide bomber the day after the failed 21 July bomb attacks.