A Pittsford man who was accused of killing his father has admitted in court papers that he committed the crime.

The admission is contained in court papers filed recently by Charlie Tan, in an effort to get a federal court to throw out his 20-year sentence on gun-related charges.

Tan’s murder trial, where he was accused of shooting his father with a shotgun, ended in a mistrial in 2015 when jurors failed to reach a verdict. Tan then pleaded guilty to charges that include having another student buy a shotgun. Tan was a student at Cornell University when his father was killed in the family’s Pittsford home.

In the affidavit filed this week, Charlie Tan says a family history of domestic violence and abuse were relevant at his sentencing but not fully presented in court. He says his father abused his mother in his presence and Tan says he eventually shot his father three times as he was sitting at his desk.

Tan says his lawyers advised him not to admit that he shot his father. He also says his attorneys did not discuss the possibility of him being interviewed or evaluated by a psychologist or specialist so that circumstances could have been presented that would help the court understand what led him to shoot his father.

Tan wants his sentence on the gun charges thrown out for what he claims was ineffective legal advice at his sentencing. There’s been no comment from the various attorneys involved in this case.