HARRISBURG, Pa. (AP) -- In an effort to keep from paying a pension to former Penn State assistant football coach Jerry Sandusky, Pennsylvania's retirement system is disputing his employment status at the time he was arrested on child molestation charges and later convicted. Attorneys for the state's pension plan argued in a filing this week that Sandusky remained a de facto school employee, collecting payments and perks even after he retired from coaching in 1999, meaning he should continue to forfeit his $59,000 annual pension, The Centre Daily Times reported Friday (http://bit.ly/1mlsZfE ). State law requires employees convicted of certain crimes to forfeit their pensions. The pension administration agency, the State Employees' Retirement System, revoked payments the day Sandusky was sentenced to 30 to 60 years in prison in 2012, waiting until then because forfeitures can't take effect until after sentencing. Sandusky's attorneys have argued in court documents and at an appeal hearing in January that their client wasn't subject to the forfeiture rules because he retired long before his 2011 arrest and subsequent conviction. The dispute centers on whether payments and other perks Sandusky received since his retirement were part of an employment contract or were simply additional retirement compensation provided by the school. Sandusky signed the agreement, under which he continued to be paid cash and football tickets and was to promote the university. He also had an office and unfettered access to the university's athletic facilities. "The letter agreement puts the lie to Sandusky's contention that he 'retired' in 1999," the state attorneys wrote in their argument. "If anything, in June 1999, Sandusky retired from his position as football coach, but then continued as (a) PSU employee in a new 'outreach' position." Sandusky's lawyers also contend that two sex crimes for which he was convicted weren't added to the list of pension-forfeiting offenses until after Sandusky retired -- though the pension attorneys said Sandusky's compensation agreement was amended in 2004, after the crimes were added to the list. Rather, Sandusky's attorneys contend any money he received after he retired from coaching wasn't payroll income, but was for speaking fees or meant to cover his travel, meals, lodging, and other expenses. Sandusky's attorney filed documents in March seeking the reinstatement of his pension. An arbiter has 30 days to decide the matter now that the state attorneys have responded. ___ Information from: Centre Daily Times, http://www.centredaily.com