NSA whistleblower's father says he has lost faith in the US justice department and his son needs a safe haven

The father of the National Security Agency whistleblower Edward Snowden says his son has been so vilified by the Obama administration and members of Congress that he is now better off staying in Russia.

Lon Snowden had been working behind the scenes with lawyers to try to find a way his son could get a fair trial in the US. Edward Snowden has been charged in federal court with violating the Espionage Act by leaking details of NSA surveillance.

But in a telephone interview with the Associated Press, the elder Snowden said he had lost faith in recent weeks that his son would be treated fairly by the justice department. He now thinks his 30-year-old son is better off avoiding the US if possible until an administration that respects the constitution comes into office.

"If it were me, knowing what I know now, and listening to advice of sage people like [Pentagon Papers leaker] Daniel Ellsberg ... I would attempt to find a safe haven," Snowden said.

As a military analyst more than four decades ago, Ellsberg leaked the Pentagon Papers, a secret study of America's involvement in Vietnam, to newspapers.

The elder Snowden said he thought Russia was probably the best place to seek asylum because it was most likely to withstand US pressure. Edward Snowden applied for temporary asylum in Russia last week.

Lon Snowden, a Coast Guard veteran who has worked on national security issues in his career, said he has tremendous faith in the American people and in the constitution. He said that in a more subdued environment his son could get a fair trial, and his actions would be considered in the context of his desire to expose a surveillance program that he and others believe exceeds constitutional bounds.

But he said the justice department's efforts to pressure other countries to turn over Snowden, coupled with silence from President Barack Obama and the attorney-general, Eric Holder, in the face of denunciations from members of Congress who have labelled Snowden a traitor, have eroded his hope for a fair trial.

On NBC's Today show on Friday, Lon Snowden said there had been a concerted effort by some members of Congress to "demonise" his son.

Lon Snowden and his lawyer, Bruce Fein, released a letter on Friday asking Obama to dismiss the criminal charges against Edward Snowden and to support legislation "to remedy the NSA surveillance abuses he revealed".

The elder Snowden and Fein said they were disgusted by Holder's letter on Friday to Russian officials promising that Snowden would not face the death penalty if he were extradited. They said it reflected a mindset that Snowden was presumed guilty and that a sentence of 30 years or life would be a reasonable punishment.

In the phone interview Lon Snowden said he had had no direct contact with his son, and knew no more about his day-to-day life in Moscow, where he is reportedly staying at an airport transit zone, than anyone else.

Lon Snowden and Fein are starting a nonprofit group called the Defense of the Constitution Foundation to promote the issues his son has raised.

"In essence, he has passed on the torch of democracy," Lon Snowden said of his son.

He said he wasn't sure there was much he could do to help his son.

"He sacrificed everything and gained nothing," the elder Snowden said. "He's done what he's done. The consequences are unavoidable, and I don't know if I can mitigate those."