The Obama administration’s struggle to bring leaker Edward Snowden home to justice keeps running into a daunting hurdle: the international fallout over Pfc. Bradley Manning’s experience in U.S. custody after his own round of secret spilling.

Snowden’s family and his supporters around the world have all argued that the tough conditions of Manning’s pre-trial confinement and the military’s unwillingness to settle for guilty pleas he offered underscore the wisdom of Snowden’s decision to remain abroad.

This week, Russia granted the former National Security Agency tech specialist asylum for at least a year and allowed him to leave the Moscow airport. The move came just days after a U.S. military judge overseeing Manning’s court martial acquitted him of aiding the enemy but convicted him of a slew of other serious charges that could put the Army intelligence analyst and admitted WikiLeaks source behind bars for the rest of his life.

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“Granting #Snowden asylum in Russia was the appropriate answer to #Manning’s guilty verdict on multiple espionage counts for whistleblowing,” German Web activist Anke Domscheit-Berg, wife of former WikiLeaks spokesman Daniel Domscheit-Berg, wrote on Twitter Thursday.

Snowden’s father said this week he’d concluded his son would not get a fair trial in part due to Manning’s treatment.

“He was subjected to inhumane conditions. He was stripped of his clothes, kept for 23 hours a day in solitary confinement, his glasses were removed. That was unacceptable,” the elder Snowden told Rossiya 24. “I just don’t have a high level of trust in our justice system, not only because of what has happened to my son.”

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Americans who’ve expressed concern about the Obama administration’s wave of leak prosecutions also see a spillover effect from Manning to Snowden in the court of public opinion and in diplomatic circles.

“The administration didn’t do itself any favors through its treatment of Bradley Manning, because the government made it a lot easier for Snowden to make the case he might be mistreated if he returns to the United States….Certainly, the optics of it are very bad,” said Elizabeth Goitein of the Brennan Center at New York University. “In terms of the scorched-earth approach to national security leaks…I think the administration dug itself a bit of a hole, and probably realizes that.”

Former State Department spokesman P.J. Crowley, whose government career came to an abrupt end after he publicly criticized the military’s decision to hold Manning in solitary confinement, said there’s no question that public opinion overseas about the Snowden saga is being influenced by the impression that Manning was abused.

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“In terms of global attitudes towards the Snowden case….there is obvious residual impact from the Manning situation,” Crowley said in an interview. “That is undoubtedly true in Europe.”

The retired Air Force officer and Clinton White House veteran said Manning’s treatment also handed a propaganda point to anti-U.S. regimes and a tool to undercut criticism of the dismal human rights records in many of those countries.

“It provides an opportunity for countries in Latin America to compete for American antagonist-in-chief,” Crowley said. “Venezuela, Bolivia, Ecuador — they define themselves in terms of willingness to stand up against the United States, and the Manning case and now the Snowden case give them an opportunity to display their street cred…. It gives them the opportunity to turn the mirror around and make a two-way conversation out of a one-way conversation.”

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It’s unclear just why Russia decided to let Snowden stay and to reject U.S. demands for his expulsion. But lately, Russian officials have been talking a lot about about Manning.

“The double standards, demonstrated by the US authorities’ in how they have approached the [Manning] situation, are raising eyebrows. If one demands others to fully observe freedom of speech, then, essentially, one should apply the same approach on himself,” Russian Human Rights Commissioner Konstantin Dolgov said Wednesday, according to the RIA/Novosti news agency.

Dolgov said his government would await the final sentence for Manning before deciding whether it would impact Snowden’s treatment in Russia, according to the Russia-backed English language site RT.

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“When the sentence is passed upon Manning for handing files to the Wikileaks website, it would be clear what would await Snowden if he returned to the United States,” Alexei Pushkov, the head of the Russian lower house’s international committee, said Monday on Twitter.

In a letter to the Russian Justice minister last week, Attorney General Eric Holder tried to dispel some of the concerns that Snowden would be mistreated if he is sent back for prosecution. Holder made no mention of Manning, but emphasized that Snowden would not face the military justice system.

“If he returns to the United States, Mr. Snowden would be brought before a civilian court convened under Article III of the United States Constitution and supervised by a United States District Judge,” Holder wrote.

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“In particular, Mr. Snowden would be appointed (or, if he so chose, could retain) counsel. Any questioning of Mr. Snowden could be conducted only with his consent: his participation would be entirely voluntary, and his legal counsel would be present should he wish it. Mr. Snowden would have the right to a public jury trial,” he said.

Some analysts say Russia would probably be taking the same stance with Snowden in the absence of the Manning backdrop.

“It’s more of a fact that Snowden is seen by [Russian President Vladimir] Putin as a good political pawn. It gives him leverage vis-a-vis this country,” Cully Stimson of the Heritage Foundation said. “He can go behind channels and say, ‘You don’t come to this with clean hands’ …but it’s like No. 10 of his talking points, and behind that he’s got nine more.”

As White House Press Secretary Jay Carney fielded questions Thursday about Russia’s decision, he stressed that Snowden would be treated fairly and humanely if the Russians send him back.

“Mr. Snowden is not a whistleblower… He should be returned to the United States as soon as possible where he will be accorded full due process and protections,” said Carney.

But the White House’s assurances on that point fall on deaf — or at least, skeptical — ears in many parts of the globe. After all, at a 2011 press conference, President Barack Obama said Manning was being treated appropriately.

“I have actually asked the Pentagon whether or not the procedures that have been taken in terms of his confinement are appropriate and are meeting our basic standards. They assure me that they are,” Obama said. “I can’t go into details about some of their concerns, but some of this has to do with Private Manning’s safety as well.”

Despite the assurances Obama was given, a military judge ruled earlier this year that the conditions of Manning’s detention were unnecessarily harsh. The judge, Army Col. Denise Lind, ordered that 112 days be lopped off Manning’s future sentence as a result.

Evidence during an extended pre-trial hearing on the subject showed that Marine Corps jailers repeatedly rejected the recommendations of Navy psychiatrists and psychologists that Manning be taken off a suicide watch that led to him being stripped for of some or all of his clothes at night and forced to sleep in an anti-suicide smock. It also emerged that Manning’s Army superiors were concerned about his treatment, but the Marine jailers had a relentless focus on keeping the high-profile prisoner alive.

A Marine Corps investigative report obtained by POLITICO in 2011 concluded that in at least one instance, officials ignored the brig’s standard operating procedures by failing to implement the psychiatric team’s recommendations. The commander of the Quantico base, Col. Daniel Choike, overruled the investigator’s finding.

In April 2011, the military moved Manning from Quantico to a larger facility at Fort Leavenworth, Kan., where he has been housed with other inmates awaiting trial.

In a report last year, the United Nations Special Rapporteur on torture said Manning’s nine months of pre-trial isolation at the Quantico brig amounted to “at a minimum cruel, inhuman and degrading treatment.”

The Justice Department declined to comment for this story. The White House did not respond to a request for comment.

American Civil Liberties Union attorney Ben Wizner said not only Manning’s treatment, but the length of the sentence eventually meted out to him will shape the global narrative about the U.S. campaign against leakers.

“There has never been a long prison sentence for someone who leaked to the press,” Wizner said. “If Manning gets a sentence of 20 years or more, it will certainly bear on not just the Snowden case, but future cases.”

Wizner said that in an era when secrets can be widely and instantaneously distributed around the world by a single person, threats of prolonged prison time might actually spur some to react by leaking.

“The U.S. is relying too much on deterrence theory,” Wizner said. “Harsh punishment might work 999 times, and the 1000^th time it might inspire a future Edward Snowden. We’ve seen in Manning and Snowden what one committed individual in that kind of system can accomplish.”

It’s clear that Snowden was aware of Manning’s case, but less clear what role that awareness may have played in determining the NSA leaker’s actions.

“Manning was a classic whistleblower. He was inspired by the public good,” Snowden said in an interview with the Guardian earlier this year.