WASHINGTON (CNN) -- The nation's capital is eagerly anticipating the testimony from former Justice Department Chief of Staff Kyle Sampson on Thursday, hoping he can answer many of the lingering questions behind the firing of eight U.S. Attorneys last year.

Sampson was the key department official in charge of deciding who should be dismissed and the main liasion with the White House over the process. Attorney General Alberto Gonzales has said that Sampson was "charged with directing the process."

Friends familiar with his expected testimony before the Senate Judiciary Committee say he will testify that he did what he was told and will defend the power of the Justice Department to be able to fire those prosecutors since they serve at the pleasure of the White House.

"Kyle is very much a supporter of the president and the attorney general," one friend tells CNN. "His main interest is in telling the truth." The friend says Sampson would "never do anything to hurt any of them" and doesn't believe his version of events will do that. Friends say Sampson believes innocent bungling was more to blame for the firestorm over the firings than anything malicious.

Friends also say Sampson will tell the truth and is not expected to go on the attack against any former officials. They say he is very quiet, very loyal and isn't the type of person who will try to "get" anyone.

What is not known is how Sampson will answer some of the key lingering questions from lawmakers such as how the specific U.S. attorneys were chosen, what specific role did the attorney general play in the process given some of the conflicting evidence and how much influence did the White House exert.

Sampson has previously said he did not resign because he had misled anyone or withheld information, but for "failing to appreciate the need for and organize a more effective political response to the unfounded accusations of impropriety in the replacement process," according to a statement his attorney, Bradford Berenson, released on March 16. The statement also said "the fact that the White House and Justice Department had been discussing this subject for several years was well-known to a number of other senior officials at the Department."