Detective Chief Inspector April Casburn was sentenced at the Old Bailey yesterday for misconduct in public office for offering to sell information to the now-defunct News of the World.
Casburn, 53, is currently in the process of adopting a child, and the judge said had that not been the case he would have sentenced her to three years.
He said her offence could not be described as whistle-blowing, and went on: "If the News of the World had accepted her offer, it's clear, in my view, that Ms Casburn would have taken the money and, as a result, she posed a significant threat to the integrity of this important police investigation."
The judge continued: "Activity of this kind is deeply damaging to the administration of criminal justice in this country. It corrodes the public's faith in the police force, it can lead to the acquittal or the failure by the authorities to prosecute individuals who have committed offences.
"We are entitled to expect the very highest standards of probity from our police officers, particularly those at a senior level.
"It is, in my judgment, a very serious matter indeed when men or women who have all the benefits, privileges and responsibilities of public office use their position for corrupt purposes."
He said he was particularly concerned about the impact of Casburn's imprisonment on her child. However, he said that had she not been arrested she would have returned to work by now, and therefore the child would be cared for by others anyway.
Casburn, from Hatfield Peverel in Essex, called the News of the World on September 11, 2010 and spoke to journalist Tim Wood about the fresh probe into phone hacking.
She claimed she was concerned about counter-terror resources being wasted on the phone- hacking inquiry, which her colleagues saw as "a bit of a jolly". The detective denied asking for money, but Mr Wood had made a note that she "wanted to sell inside information".
Mr Justice Fulford said: "It seems to me Mr Wood was a reliable, honest and disinterested witness."