Charles "Charlie" Tan sold marijuana and psychedelic mushrooms to Cornell University students and, weeks before the killing of his father, received a significant shipment of marijuana from California, federal prosecutors say.

"Tan's phone records confirm that he sold marijuana to other students (charging $200 an ounce), had received a 5-pound shipment of marijuana for $12,000 in January of 2015, and that he also sold psilocybin mushrooms, and DMT, both of which are psychedelic drugs," according to a court filing from Assistant U.S. Attorney Lisa Fletcher, who is prosecuting Tan on gun crimes.

DMT is a powerful hallucinogen.

In a pre-sentencing court filing this week, prosecutors say that they retrieved this information from a cellphone of Tan's, which had been difficult to unlock. Earlier this year, prosecutors received a warrant to search the cellphones of Tan and his mother, Fletcher wrote.

According to the court filing, new technology allowed the contents of the phones to be extracted.

"Even with newer technology, this was no small task," Fletcher wrote. "It took weeks, and thousands of dollars, to have the phones unlocked, and their contents extracted."

Tan is scheduled to be sentenced later this month in Syracuse for his role in the illegal purchase of the shotgun used to fatally shoot his father in February 2015. Tan, who duped a friend into buying the gun for him, has pleaded guilty to federal crimes, including his knowledge that the gun would be used in the homicide.

The Democrat and Chronicle has reached out to Tan's attorneys for comment.

Tan was arrested in February 2015 and accused of the killing of his father, Liang "Jim" Tan. He was tried later in 2015 and the jury could not reach a verdict. James Piampiano, then a county court judge, later dismissed the criminal indictment, saying there was not enough proof to even bring Tan to trial.

An appellate court ruled that Piampiano's decision could not be reversed, though the appellate judges said Piampiano was clearly wrong on the law.

In September 2017, Tan was arrested and accused of assistance with the illegal shotgun purchase; his friend, Whitney Knickerbocker, lied when he bought the shotgun. Knickerbocker claimed the gun was for him when he instead purchased it for Tan.

U.S. District Judge Frederick Scullin Jr. is scheduled to sentence Tan on Nov. 19.

Court records say that federal sentencing guidelines, which are advisory for judges, recommend a 25-year sentence for Tan, who has been jailed since his 2015 arrest. His attorneys are arguing that a five-year sentence would be fair.

Tan has maintained that his father was abusive to his mother, and had shown a willingness to kill his mother — Qing "Jean" Tan — days before the homicide.

In court filings, friends of Tan describe him as a giving young man who was always there when help was needed. There is also support for the allegations of abuse, including reports that Qing Tan was moved by police in Canada to a shelter because of abuse. Her sons, Charles and Jeffrey, were then very young. Also, days before Liang Tan was slain his wife called police, saying that her husband had choked.

One woman who was a neighbor of the Tans in Pittsford wrote in a letter to Scullin that she often saw Qing Tan with bruises on her arms. Liang Tan was typically controlling, and once grew angry, canceling his wife's credit cards and telephone, the neighbor wrote.

Another neighbor also said in a letter to the judge that she saw Qing Tan bruised from abuse by her husband. "Liang would go on rampages and throw and break things and leave it for Jean to clean up and fix," the neighbor wrote.

In a letter to the judge, Tan seemed to hold himself responsible for the homicide, without admitting to it.

"All I knew was that my mother was unusually defeated, and repeatedly told me that (Tan's father) was going to kill her," Tan wrote in an Oct. 24 letter to Scullin. "I felt like there was no other option, that I had to protect her. Rather than digest the situation, and other possible alternatives, I acted on impulse, leading to my series of immature and irrational decisions."

Fletcher wrote in her filing this week that Tan should not receive a sentencing break for what she said was premeditated murder.

"He was an accomplished Ivy League student, varsity athlete, social chair of his fraternity, and ran a business selling drugs on campus," Fletcher wrote. "He was old enough, mature enough, and smart enough to understand and appreciate the gravity, and ramifications, of murder.

"And this murder was not impulsive. (Tan) devised a plan, and took great steps to carry it out."

Tan, who is a Canadian citizen, will likely be deported at the end of his sentence — whatever its length.

GCRAIG@Gannett.com

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