The life sentence given to a soldier convicted of trying to provide Al Qaeda (search) with information on the U.S. military almost guarantees the National Guardsman will appeal, legal experts said Friday.

Spc. Ryan G. Anderson (search), 27, a tank crew member whose 81st Armor Brigade unit is now in Iraq, was convicted Thursday on charges a military spokesman said amounted to attempted treason. The terrorists he thought he was meeting with were undercover federal agents, prosecutors said.

A jury of nine commissioned officers from Fort Lewis (search) recommended a sentence of life in prison with the possibility of parole, and dishonorable discharge. The maximum term would have been life without parole.

Based on defense arguments of mitigating mental illness, military law expert David Sheldon said Anderson likely would have a good chance of reducing his sentence.

Another military law expert, Eugene R. Fidell, said the officers' decision not to impose the maximum term suggested defense lawyers' contention that Anderson's judgment was distorted had some impact.

Mental health experts testified during Anderson's four-day court martial that he suffered from bipolar disorder and Asperger's syndrome, a relatively mild form of autism that impairs cognitive and social functioning.

Fidell said Anderson's penalty likely would be reduced. "It's one of the purposes of the appellate review," he said, "to try and cut back on what might be abhorrent sentencing."

A call to Fort Lewis officials was not immediately returned.

Anderson's defense team has 10 days to review the trial record, which then must go through further reviews lasting four to six months before a sentence is imposed. The sentence recommendation is reviewed by the post commander.

If the post commander approves a sentence of more than one year, the U.S. Army Court of Criminal Appeals must then also review the trial record, Fidell said. The appellate court has the authority to decide whether the conviction and sentence are appropriate.

Further appeals could go before the Court of Appeals for the Armed Forces, which is made up of civilian judges appointed by the president, and if necessary, the U.S. Supreme Court.