McMahon’s social media presence had already gained notoriety in Chapel Hill, Charlottesville and elsewhere.
McMahon has been highly active on social media sites like Gab, which has been criticized as a platform for bigotry and radicalization, and where his “Jack Corbin” account had more than 2,000 followers.
The Corbin account was no longer available on Gab as of Wednesday evening, though it was online earlier that day.
After Robert Bowers allegedly murdered 11 people in a Pittsburgh synagogue with anti-Semitic motives last October, a Southern Poverty Law Center analysis found that Bowers had re-posted and replied to Gab posts by Corbin more frequently than he did any other user. A Gab post by Bowers shortly before the synagogue shooting closed with, “Screw your optics, I’m going in.”
Corbin has since praised Bowers on Gab for the slaughter.
McMahon has often used his Corbin account and other aliases, including the names “Pale Horse” and “Dakota Stone,” to publicly identify and antagonize UNC students. He has commonly targeted students, mostly women, for their public opposition to Silent Sam, using derogatory claims about their appearance, race, and other personal attacks.
One target of that harassment has been UNC graduate student Lindsay Ayling. In past posts, McMahon mocked the death of Ayling’s brother.
“How’s what’s left of what remains of your late little brother ... who succumbed to his alcoholism and obsessive love for trains?” McMahon said in a Facebook comment in July, responding to a post by Ayling through a page he started called “Restore Silent Sam.”
After a group of pro-Confederate protesters came to UNC last May to advocate for Silent Sam’s return to campus, McMahon posted through his Corbin account on Gab that he was giving control of the Restore Silent Sam page to “some brave activists who stood against Antifa in Chapel Hill.”
The Facebook account’s comment months later toward Ayling about her brother’s death and other posts indicate that Corbin maintained control of the Restore Silent Sam page, but began sharing it with individuals who have gained their own notoriety through actions on campus.
At the end of May, McMahon said in a Gab post on his Corbin account that, “Nancy Rushton makes a damn good admin too!” The woman McMahon referred to is Nancy McCorkle, who has attended multiple Silent Sam protests at UNC and was recently found guilty of vandalizing the Unsung Founders Memorial, a campus monument, with slurs and urine.
Ayling said that during the May demonstration, McCorkle began making train noises to her in reference to her brother’s death. She said Ryan Barnett — who was also found guilty for vandalizing the Unsung Founders Memorial — taunted her about it as well.
“They were kind of taking instructions from Jack Corbin about how to harass people,” Ayling said.
McCorkle and Barnett have traveled to UNC before to advocate for Silent Sam’s return with the Heirs to the Confederacy, an out-of-town group that has received criticism and community response for its members' open-carrying of guns and other weapons on and around campus grounds.
In the months leading up to McMahon’s arrest Wednesday, he had been posting on Gab through the Corbin account about his ongoing development of a video game that would be of simple-enough quality for any user on Gab to play on their own computer.
The game, he said, would be a first-person shooting game “which promote(s) fascism, and where you kill Antifa in the game.” It would include 3D maps of cities including Charlottesville, Chapel Hill and Carrboro. He said he planned to model the shooting targets of the game as “Antifa” he knows the faces and names of.
“I’ll likely change their names so I don’t get sued by them for making them a video game character to be slaughtered in-game without paying them royalties,” McMahon said in the post.
McMahon posted periodically since that time with updates on the game. A week before his Wednesday arrest, McMahon said he had released a newly testable model of the game but wasn’t posting it on Gab because of “Antifa terrorists” monitoring his page.
The Justice Department declined to comment beyond its press release and indictment, saying Wednesday evening that McMahon would be “arraigned in court shortly" in an email to The Daily Tar Heel.