Charlie Tan could be facing up to 25 years in federal prison when he’s sentenced next month on gun charges connected to the death of his father, Jim Tan, in 2015.

New sentencing guidelines released by the prosecutors say Tan could receive up to 10 years for each charge of receiving a firearm with intent to commit an offense and for causing someone to make a false statement when buying a firearm.

Tan also can receive a maximum sentence for a second coercion charge.

In June, Tan pleaded guilty just before his trial on weapons charges was scheduled to begin. He admitted at the time to getting a school friend both to buy a shotgun and to lie about it.

In new documents released Friday, the prosecution explains its sentencing arguments, including new details about what investigators say happened in the hours after they believe Tan shot and killed his father.

According to the 15-page document, Tan’s mother Jean bought one-way tickets to China, but instead of taking the trip, they returned to the Pittsford home where Jim Tan’s body remained at his desk, days after his death.

The prosecution says that “while the defendant may argue that he is not before this court to be sentenced for murder, his sentencing guidelines are driven by that crime, as he set out not just to purchase a shotgun, but to obtain a murder weapon.”

The document states that the combined maximum statutory sentences on all of these counts could total up to 300 months – a total of 25 years.

Tan is scheduled to be sentenced on November 19.