They say Eister was less culpable than at least one witness granted immunity in the case.
Eister helped destroy e-mail evidence at Fumo's Harrisburg office over four days in June 2004. He and others knew the FBI was investigating Fumo.
Fumo faces sentencing in July for his March conviction on 137 corruption counts.
Another former aide, Leonard Luchko of Collingdale, was sentenced Wednesday to 30 months in prison for his larger role in destroying e-mail evidence.
Get Action News on your website
