His plea makes Griles the highest-ranking Bush administration official to be convicted in the scandal surrounding Abramoff, who is at the center of a corruption ring that has also involved lawmakers and federal officials. Abramoff has already admitted to using his connections in the Interior Department to benefit his Indian tribal clients.
Under the plea agreement, Griles admitted to testifying falsely before the Senate Indian Affairs Committee on Nov. 2, 2005, and also during a deposition on Oct. 20, 2005.
He told the Senate committee it was "outrageous and is not true" that Abramoff had any special access to him at the Interior Department and told committee investigators that his relationship with Abramoff was "no different" than his relationship with other lobbyists.
"I am sorry for my wrongdoing. I fully accept the responsibility for my conduct and the consequences it may have. When a Senate committee asks questions, they must be answered fully and completely and it is not my place to decide whether those questions are relevant or too personal. I apologize to my family, my friends, the committee and its staff," Griles said in a statement, according to the Associated Press.
According to investigators, Abramoff and Griles were introduced in 2001 through Griles' then-girlfriend, Italia Federici, a Republican environmental activist. Abramoff directed his tribal clients to give $500,000 to Federici's Council of Republicans for Environmental Advocacy between March 2001 and May 2003.
Although Griles admitted misleading investigators and Congress, prosecutors dropped earlier allegations that he did anything improper to help Abramoff, and the agreement does not require the former Interior Department official to assist investigators in their grand jury probe. Sentencing is scheduled for June 26.
Federal prosecutors agreed to propose no more than a 10-month prison sentence that would allow Griles to spend half the time in a half-way house or under house arrest. The maximum sentence Griles could face is five years and a $250,000 fine.
Assistant Attorney General Alice Fisher told the AP the case shows the Justice Department is willing to go after "public corruption at all levels of government."
Others convicted in connection with Abramoff include former Rep. Bob Ney, R-Ohio, former White House official David Safavian. Abramoff is already serving six years in prison for a casino deal in Florida, but he is awaiting sentencing in the Washington scandal.