Published Wednesday, 12 December 2012
Edward Devenney, 30 and from NI, pictured at an earlier court appearance. (© PA)
Edward Devenney, 30 and from Co Tyrone, was sentenced at the Old Bailey on Wednesday - where he was told that he had betrayed his country and his colleagues.
Mr Justice Saunders described it as a "very serious" case and said that Devenney had known what he was doing when he met with the men in January.
"He did supply details of movements and operations carried out and to be carried out by nuclear submarines," the judge said.
"I am satisfied that in the wrong hands it was capable of affecting the operational effectiveness of nuclear submarines."
No actual damage was done to national security because, unknown to Devenney, the men were undercover MI5 intelligence officers.
This was a classic story of betrayal ...
Mari Reid, CPS counter-terrorism division
The court previously heard how Devenney had contacted the Russian Embassy in November last year, then gathered intelligence two days later from on board the HMS Vigilant.
He got into a locked safe and took photographs of part of a secret code for encrypted information.
Devenney pleaded guilty to breaching the Official Secrets Act by gathering classified information and to misconduct by meeting the supposed spies.
Outside court, a statement was read on his behalf.
"I am deeply sorry for the hurt and shame that I have brought on my family and loved ones," it said.
"Prior to these events I gave the Royal Navy 11-and-a-half years of service and I deeply regret my actions and the effect they have had on the Submarine Service and colleagues."
Prior to sentencing, the court heard that Devenney had been "something of a blue-eyed boy" in the Royal Navy until a rape allegation - of which he was later cleared - was made against him in 2010.
At the time of the secrets breach, he was said to have been drinking heavily, suffering from depression, and to have felt hard done by after failing to secure a promotion.
He had been warned that he would be discharged from the Navy if his absences without leave continued and if his conduct, which had declined following the rape allegation, did not improve.
"Edward Devenney was employed by the Royal Navy to protect this country from potential threats to our security. Instead, he pursued a course of conduct likely to put his country at risk," Mari Reid, unit head for the CPS counter-terrorism division, said.
"We rely on the men and women of our armed forces to keep us safe. It is hard to imagine a greater breach of that role than Devenney's actions."