Last September, plans to name a post office in Las Vegas after a World War II veteran were revoked - and it was later found out that he had lied about being awarded a Silver Star medal.
The problem of 'military imposters' falsely claiming decorations and medals is not new - but it is a growing problem, according to the New York Times.
"This kind of fraud matters," Doug Sterner, a decorated former Army sergeant, told the newspaper.
"Because it cheapens the valour of service, warps the historical record and scams taxpayers of millions of dollars in veteran's benefits."
The problem is difficult to police, as charlatans are easily able to find fake military documents, medals and uniforms on auction sites.
And verifying claims of military service and awards is difficult because no official database exists - and this has led to a number of embarrassingly and potentially costly blunders.
In April, the Associated Press found that the U.S. Department of Veterans' Affairs was paying disability benefits to 966 supposed prisoners of war from the Vietnam War.
But official records show that there are actually fewer than 600 still alive.
In response, U.S. Congress is calling for an investigation of the veterans' department - "to analyse and verify the accuracy of the data," according to Katie Roberts, department spokeswoman.
A pending bill will also seek to make verification easier by requiring the Defense Department to create an online database.
Over the past decade, Doug Sterner has built his own database of 120,000 valour medal recipients going back to the Civil War.
For the time being, an FBI department handles stolen valour cases.
An a online network of volunteers, including many veterans, is also helping to combat faint claimants.
The network combs newspapers, examines military files and gains help from employers, biographers and obituary writers, according to the New York Times.
False valour claims can be made by people in high places.
In 2007, Robert W. Levy, a former mayor of Atlantic City, resigned after revelations that he lied about being a Green Beret and about being awarded combat infantryman and parachutist badges.
Mr Levy, a decorated Army veteran with 20 year service, said that he did work with the Green Berets, but, over time, the experience led him to start making claims that he had been in the unit.
"It was wrong, and I should have corrected it ages ago," he said. "I ruined my life with those claims," he said.