Wayne Simmons, 62, had been a Fox News commentator on the basis of his claim that he spent 27 years working for the Central Intelligence Agency.
As part of a plea agreement filed in federal court in Virginia, Simmons admitted he defrauded the government to gain access to a US Army training program in 2008 and to be deployed to Afghanistan as a senior intelligence advisor, the Justice Department said in a statement.
"Mr. Simmons lied about his criminal history and CIA employment in order to fraudulently obtain government contracts, and separately, defrauded a victim through a phony real estate investment deal," said Paul Abbate, assistant director of the FBI's Washington field office.
"With these criminal actions, Mr. Simmons abused the trust of others, both in and outside of government, for his own personal financial gain."
Simmons, indicted on criminal charges last October, also pleaded guilty to unlawful possession of firearms, officials said.
According to the indictment, Simmons falsely claimed to have worked as an "outside paramilitary special operations officer" for the Central Intelligence Agency from 1973 to 2000, and used that false claim to attempt to obtain government security clearances.
He ended up working for three government contractors -- not identified in the indictment -- and was paid on the basis of "materially false and fraudulent pretenses," the indictment said.
Simmons also co-authored a spy novel that appeared to have been loosely based on his purported exploits, which is sold on Amazon.Com.
