Mr Galley faces a disciplinary hearing at work
The civil servant arrested for leaking Home Office documents to the Tories has said he does not regret doing so as he believed it was in the public interest.
Christopher Galley also told the BBC he was only responsible for four of the 20 documents leaked over two years.
Mr Galley and the MP who received the papers have been told they will not be charged, after a five-month inquiry.
The Tories are demanding a Commons statement from the home secretary, who has defended involving the police.
Damian Green, the Conservative immigration spokesman who received the leaks, said ministerial embarrassment about the stories he was revealing had led to his arrest.
An MPs' investigation also suggested civil servants may have exaggerated the threat to national security caused by the leaks, owing to frustration at being unable to find the source of them.
Announcing the decision not to charge either man, Director of Public Prosecutions Keir Starmer said he had decided there was not enough evidence for a realistic prospect of conviction as the material "was not secret information or information affecting national security".
Mr Galley, who also learned on Thursday that he would not face charges, told the BBC he that while he expected to be sacked at an upcoming disciplinary hearing, he felt he had been "justified" in releasing the information.
"I think the public needed to know that certain aspects of the immigration system were in, what I would term as, disarray," he said.
He said he had not had access to any "top secret" documents and had only leaked four documents - while the Home Office believed 20 had been leaked.
"I don't have any particular regrets about what I have actually done but the only real regret I have is not taking a solicitor into the police interview," he added.
Series of leaks
Newspaper reports on Friday suggest Ms Smith's authority had taken a blow over the affair, which comes after controversy over her second home expenses but Home Office minister Vernon Coaker denied her job was on the line.
He told the BBC: "I absolutely think she can keep her job. She's doing all she can to tackle the issues of today."
However, shadow home secretary Chris Grayling said she must make a Commons statement on the leaks inquiry, when MPs return from their Easter break on Monday.
Ms Smith said it would have been irresponsible not to have acted
He said: "The past few weeks have been a chapter of chaos in the Home Office. Jacqui Smith should be making a wide-ranging statement so MPs can question everything that is going wrong. If she doesn't she is running scared."
But aides told the BBC Ms Smith would not be making a statement on the investigation as it was a matter for the police, who operated independently.
A series of leaks in 2007 and 2008 included information about illegal immigrations who got security jobs in Britain, an illegal immigrant working as a cleaner at the House of Commons and predictions that the recession would lead to a rise in crime.
The inquiry led to concerns the police were being used to silence whistleblowers but Ms Smith has defended her department's role saying it would have been "irresponsible" not to have acted.
"My job is to protect the British people. It is also to protect the sensitive information about how we protect them as well and that is what we have done," she said.
Former Lord Chancellor, Lord Falconer told BBC Radio 4's Today programme that Ms Smith's job should not be under threat as she probably thought she was following normal procedure.
"There is obviously damage in the sense that the papers are being critical but I think it is unfair to Jacqui Smith," he said.
"She was doing what was believed to be the normal thing and I think what is now required is for the Cabinet Office to change their guidance in the circumstances in which police can be called in."
And former home secretary David Blunkett told BBC Radio 4's The World At One: "I think there's not a home secretary in recent history who hasn't found themselves at the end of a week wondering why they're doing the job...
"You just have to take a deep breath, not because of arrogance but because you do need the self-confidence to carry on."
Mr Green was arrested in November and held by police for nine hours on suspicion of "conspiring to commit misconduct in a public office, and aiding and abetting, counselling or procuring misconduct in a public office".
He said police officers told him if convicted he could face life in jail and said he was simply doing his job in exposing "the many failings of the government's immigration policy".
A review of the methods used when police raided Mr Green's home and his Commons and constituency offices was carried out by British Transport Police Chief Constable Ian Johnston, but has not been published.