A fighter pilot who mistakenly bombed Canadian soldiers in Afghanistan last year, killing four, refused to accept the Air Force's offer of lesser charges Wednesday and will face a court-martial.

It wasn't immediately clear what charges Maj. Harry Schmidt will face in the military trial. The Air Force could prosecute him on involuntary manslaughter, aggravated assault and dereliction of duty charges, with a possible prison term of 64 years if convicted.

Schmidt rejected the Air Force's offer that he could instead face an administrative hearing with possible punishments including a reprimand or forfeiture of one month's pay.

His lawyer, Charles W. Gittins, said in an emailed statement that the pilot believed he could not get a fair administrative hearing. The hearing would have been overseen by Lt. Gen. Bruce Carlson, who Gittins said has already determined Schmidt is guilty. Carlson on Tuesday refused to recuse himself from the case.

"Imposition of punishment in my case is a foregone conclusion," Schmidt wrote in his response to the Air Force's offer. He cited a June 16 memo from the 8th Air Force to Air Force headquarters that refers to Schmidt's "lack of judgment ... and his violation of flying regulations and procedures."

An Air Force spokeswoman did not return calls for comment Wednesday. In a written statement, the Air Force said a trial date and judge have not been determined.

Carlson last week recommended the administrative hearing for Schmidt. At the same time, he recommended dropping charges against Schmidt's partner in the mission, Maj. William Umbach, and allowing Umbach to retire.

The two Illinois National Guard pilots had been the first Air Force pilots to face the possibility of homicide charges as a result of friendly fire during combat.

Schmidt, 37, has maintained he did nothing wrong, saying the Air Force gave him no warning that allies would be performing live-fire exercises the night of April 17, 2002, when he dropped the laser-guided bomb. He said he mistook the Canadians for Taliban fighters.

The bombing near Kandahar killed Sgt. Marc Leger, Pvt. Richard Green, Cpl. Ainsworth Dyer and Pvt. Nathan Smith and wounded eight other Canadians. They were the first Canadians to die in combat since the Korean War.

The case against the two US pilots has been closely watched in Canada, where many were outraged by the bombing and the two days it took President Bush to publicly apologize.

Relatives of the Canadian soldiers were disappointed when Carlson last week recommended that Schmidt face lesser charges of dereliction of duty in an administrative hearing. In an administrative hearing, Carlson would have considered allegations that Schmidt failed to ensure that the troops he attacked were not allies and did not obey when air controllers told him to "stand by" before he dropped the bomb.

Carlson also recommended that a flying evaluation board determine whether Schmidt should be allowed to fly for the Air Force again.

Schmidt had transferred to the National Guard in 2000 after a decorated career as a Navy pilot and an instructor at the Navy's "Top Gun" fighter pilot school. Umbach, 44, is a United Airlines pilot who had served in the Air Force.