This wasn’t an episode of The Sopranos come to life, the lawyer for the man who killed a mob boss earlier this year suggested in a court filing Friday.

No, it’s much stranger. The alleged killer, his lawyer said, is a believer of the QAnon conspiracy theory who thought he could count on President Donald Trump’s “full support” when he drove up to the Staten Island home of Gambino boss Francesco “Franky Boy” Cali.

In a court filing first reported by The New York Times and provided in full to TPM by the defendant’s lawyer, Anthony Comello is portrayed as a devout Trump fan whose participation in the QAnon conspiracy theory “evolved into a delusional obsession” and “permeated every aspect of the defendant’s conduct and dictated his actions.”

Noting his intent to present evidence of mental disease or defect in his client, attorney Robert C. Gottlieb wrote that Comello didn’t understand that killing Cali was wrong — and also that he only intended to place Cali under “a peaceful citizen’s arrest.”

Comello viewed the man he killed as “a prominent member of the Deep State” who held “a significant status in a worldwide criminal cabal bent on the destruction of American values and the American way of life,” Gottlieb wrote.

The alleged murderer planned on delivering Cali to the military, as he believed traditional law enforcement to have been corrupted by the Deep State, his lawyer said.

The QAnon conspiracy is a sprawling and loosely connected series of anonymous posts that together form the basis for a vibrant online community. Thousands collectively interpret the information drip from “Q,” a supposed knowledgable insider, with the vigor of talmudic scholars. The conspiracy asserts at its base that President Trump is engaged in an underground struggle with the “Deep State,” which in turn is accused of various criminal enterprises including child sex trafficking. Recently, Q believers ruined the normally peaceful Earth Day celebration in Grass Valley, California.

At his first hearing in March, Comello showed up with a big “Q” scrawled on his hand.

Comello, his lawyer asserted, believed “he had been given secret knowledge about the Deep State” and was destined to play a “grand role” in the ongoing conflict.

The downward spiral started, Comello’s lawyer said, after Trump’s election, when Comello’s family “began to notice changes to his personality.”

“He began to take an interest in politics, something he had not previously been involved in,” Comello’s lawyer wrote. “Approximately five to six weeks prior to the incident which gives rise to this case, Mr. Comello, the defendant in this case, became increasingly vocal about his support for ‘QAnon.'”

“Because of his self-perceived status in QAnon, Mr. Comello became certain that he was enjoying the protection of President Trump himself, and that he had the president’s full support,” Gottlieb wrote later.

Part of Comello’s perceived duties apparently involved placing supposed members of the Deep State under citizen’s arrest: Earlier this year, Comello attempted to make citizen’s arrests of New York Mayor Bill De Blasio and Reps. Maxine Waters (D-CA) and Adam Schiff (D-CA), Gottlieb wrote, but was “rebuffed” by law enforcement when he asked for their help. The Times reported that it confirmed these incidents with unnamed law enforcement officials.

Gottlieb said Comello’s attempted citizen’s arrest on Cali, which turned into a deadly shooting, began with Comello backing his car into Cali’s Escalade. When Cali came out to inspect the damage and allegedly shook hands with Comello, Gottlieb said Comello informed Cali of his intent to arrest him.

After Cali made a “furtive movement in the vicinity of his waistband,” Comello feared for his life and shot and killed the Gambino boss, the lawyer said.

Comello’s lawyer listed two Instagram accounts he said belonged to Comello. One, amello_0908, is set to “private” but includes a link to an edited video of motivational lines from President Trump. The other, realamericasvoice_, is public and includes several walls of text typical of Q-believers, and frequent attacks against Democrats, Muslim Americans, undocumented immigrants and others.

The local prosecutor’s office did not return TPM’s request for comment Monday.

Read Gottlieb’s filing below:

Correction: This post initially referred to the man who fired a gun in Washington, D.C.’s Comet Ping Pong in 2016 as a QAnon believer. In fact, that restaurant was the subject of the so-called “Pizzagate” conspiracy theory, which pre-dated QAnon.