Before pulling the trigger, the professor was thoughtful.

Mark J. Bird had been at the College of Southern Nevada for more than two decades in the department of human behavior. He had a feel for the rhythms of the school day, the timetables of when students filled the hallways or were tucked into classrooms. But as the 69-year-old arrived at the campus west of the Las Vegas Strip on Aug. 28, the sociology professor was not there to deliver a traditional lesson.

He arrived around 8 a.m., a police report obtained by The Washington Post would later state. The desert sun was already pounding the parking lot asphalt, hoisting the local temperature into the 90s. The school’s K Building, a blocky, modern structure surrounded by a cracked horizon of mountains in the distance, was stirring for early morning lectures. Hefting a black briefcase, Bird made his way to the building’s second floor.

His choice was purposeful, Bird would later tell police investigators. It was a Tuesday, the second day of the semester. There probably would not be many students around.

Still, Bird waited for the hallway to clear before entering a unisex bathroom. He locked the door. He taped a $100 bill and a note — “For the janitor” — to the mirror. He placed three sealed letters on the counter. He then pulled the gun from his case, a recently purchased .22-caliber Cobra Derringer. It was a tiny, two-shot pistol, like something an Old West riverboat gambler would hide in a vest pocket.

From the bathroom, a loud bang jolted the hallway, witnesses would tell police. A burning sensation crawling up his left arm, ears screaming, Bird popped out of the door, blood gushing from his left forearm, he said later. Bystanders flocked to his side. The smell of gunpowder drifted on the air. Someone tried to stop the bleeding with paper towels from a nearby maintenance cart. The panic button was punched. Medics and police arrived.

The pain did not muzzle Bird. In fact, the words spilling from the professor had a pointed political edge, police said. As one witness told investigators, Bird “started saying he’s protesting [President] Trump and that he shot himself because of that.”

Bird’s anti-Trump rhetoric would continue in his interviews with investigators. Although the professor survived his injury, he is now facing criminal charges stemming from the shooting, including felony counts of carrying a concealed weapon without a permit and discharging a gun in a prohibited area. Court records indicate he has yet to enter a plea.

Bird, who remains in custody, has not publicly filled in the motivations behind the episode. His attorney also did not return a call for comment. But in his interviews with police, as well as his writings left behind at the scene, the professor cited concerns over the environment and gun control as factors throwing him over the edge. The act places Bird among an extreme set of individuals who turn to public self-harm as an outlet for anxiety and anger over current events.

Suicide or self-harm linked to a larger political agenda goes back thousands of years.

Michael Biggs, a University of Oxford sociologist, defines “self-immolation” as “an individual intentionally killing himself or herself (or at least gambling with death) on behalf of a collective cause.” He notes: as “an act of protest, it is intended to be public in at least one of two senses: performed in a public place in view of other people, or accompanied by a written letter addressed to political figures or to the general public.”

The act was literally burned into the wider American consciousness in the 1960s as Buddhist monks set themselves on fire to protest the South Vietnamese government. Journalist David Halberstam memorably recounted an episode in June 1963 when monk Thich Quang Duc set himself ablaze in Saigon, a sight that left the veteran correspondent “too shocked to cry, too confused to take notes or ask questions, too bewildered to even think.”

Biggs’s own research documented “533 individual acts of self-immolation — including attempts which did not prove fatal — from 1963 to 2002.”

The Trump era — a time period as fraught with high-wattage divisiveness as the 1960s — also has seen public spectacles of self-immolation. In April, New York City gay rights attorney David Buckel set himself on fire in Brooklyn’s Prospect Park. A note found on the body stated he had taken his own life to protest environmental destruction, The Washington Post reported.

Similarly, personal and political despair contributed to the July death of Mahmood Salem. According to NBC News, the Yemeni-American citizen was distraught when he learned his wife and two children would not be allowed back into the country due to the president’s controversial travel ban. He committed suicide.

“I’ll say it’s the first and main reason. Maybe there is other stuff, but I could give it 90 percent,” his brother told NBC. “He cannot bring them here and at the same time, he cannot take them back to Yemen because it’s war.”

In his interview with investigators from a hospital bed, Bird made it clear he was not attempting to kill himself or to harm others. He waited until the hallway was clear so no one was in the line of fire, he explained. He purposely shot his left forearm so he would survive the blast, he added.

Investigators still pressed Bird for a motive.

“Bird stated that there were many reasons for what he did today, but the main reason why he shot himself was due to the fact that he is upset with the way President Trump was running our country,” an officer wrote in the police report obtained by The Post. “He stated that he did not agree with the policies that Trump had put in place and he felt someone needed to take a stand to prove a point.”

More clues to his thinking were contained in the sealed letters recovered from the bathroom sink. One, addressed to the college’s president, Federico Zaragoza, begins with Bird “sincerely” apologizing “for my behavior today.”

“I was motivated by multiple reasons,” he wrote. The note then pointed to an Oct. 20, 2017, CBS News story. “[T]he Earth had roughly 100 million malnutrition and pollution deaths in the past decade — and the Earth is on a course for at least another 100 million such deaths in the next decade,” the professor wrote. “One hundred million deaths are more than all the military and civilian deaths of WW2.”

A “less significant” factor in his decision was the Oct. 1, 2017, mass shooting in Las Vegas, Bird wrote. “Since this incident, there has been no national legislation banning bump stocks, banning civilian ownership of AR-15 type assault weapons, and the passage of universal gun background checks legislation. Apparently, it is about as easy to buy an AR-15 as a 2-shot derringer.”

The police report stated that during his interview with police, Bird became so emotional, his voice clogged with tears and his breath coming up shallow, that investigators had to steer the topic away from politics or the shooting until the suspect regained his composure. He also reiterated to police “he did not shoot himself in protest, but rather to promote better gun control,” investigators wrote.

“Bird stated that he believed that by shooting himself he was able to effectively deliver the message he intended to deliver.”

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