PHILADELPHIA (REUTERS) - Bill Cosby's lawyers on Tuesday (June 25) appealed his Pennsylvania conviction for drugging and sexually attacking former Temple University administrator Andrea Constand at his home near Philadelphia 15 years ago.

Attorneys for the once-beloved American actor and comedian, star of The Cosby Show, submitted a written appeal of the 2018 guilty verdict to the Pennsylvania Superior Court, calling for either a new trial or dismissal of the conviction altogether.

The 348-page document said Cosby, 81, was wrongly convicted on the basis of "flawed, erroneous, and prejudicial rulings" by the trial judge, including allowing testimony from several accusers other than the woman he was charged with assaulting in the case.

The appellate brief also challenged the propriety of the trial judge's decision to allow the jury to see incriminating admissions by Cosby from a sworn statement he had once given in an unrelated civil case brought by another accuser.

Cosby was convicted in April 2018 of attacking his one-time friend, Constand, a former women's basketball coach, in his suburban Philadelphia home in 2004. A jury in Montgomery County courthouse in Norristown, Pennsylvania, found him guilty of three counts of aggravated indecent assault.

He is serving a three- to 10-year sentence at the maximum-security SCI Phoenix facility outside Philadelphia.