WARWICK, R.I. -- It happened a few minutes before the beginning of Jim Langevin's junior cadet shift back in 1980.
He arrived at the police station here early, as usual. Two officers were standing in the locker room admiring a new .45-caliber semiautomatic pistol. Thinking the chamber was empty, one of them pulled the trigger. A bullet ricocheted off a locker and went right through the boy's neck, severing his spinal cord.
At 16, he would never walk again and never fulfill his dream of becoming a police officer.
Now, three decades later and seven terms into his career as one of Rhode Island's two members of the House of Representatives, Mr. Langevin, 48, is the only quadriplegic ever to serve in Congress. And his story, unknown to many of those who work with him every day in the Capitol, has thrust him into the raging national debate over gun control.
For the past month, he has been on a quiet campaign to persuade his colleagues to give up their guest passes to next Tuesday's State of the Union address by President Obama to victims of gun violence.
That way, he said, when the nation's highest office holders look up from the floor of the House to those watching from the gallery, they will not be able to avoid seeing the human toll that guns can extract.
"It's a powerful reminder to every member of Congress how pervasive this issue is," he said the other day as pulled his electric wheelchair up to a coffee table in his district office. So far he has nearly 20 takers, and many more who are considering the idea.
Mr. Langevin (pronounced LAN-jih-vin), who has boyish looks, a soft voice and an imperturbable demeanor, may not be the highest-profile Democrat pushing for more gun control. And he is not the only member of Congress with a tragic personal history involving a gun.
Those stories abound. Carolyn McCarthy, Democrat of New York, lost her husband in the 1993 Long Island Rail Road rampage that also critically injured her son. The 20-year-old nephew of Elijah Cummings, Democrat of Maryland, was shot to death in his apartment in 2011. Bobby Rush, Democrat of Illinois, lost his 29-year-old son to a shooting in 1999.
But like no one else in Congress, Mr. Langevin serves as what he calls "a visible symbol" of the danger of weapons.
"I think when I speak about it," he said, "at least it gets them to pause and think. It makes it real, the damage that guns can do."
Supporters of stricter gun laws say they see a small window of time in which to act. Mindful of how quickly Washington's attention can shift, they say they hope Mr. Langevin serves as a conscience check to politicians who are on the fence.
"Jim's wheelchair is a startling reminder of the danger of a bullet," said Representative Keith Ellison, a Minnesota Democrat who is helping to recruit other members to join the State of the Union effort. Mr. Ellison has given his ticket to Sami Rahamim, the son of a man who was among seven people killed after a workplace shooting in Minneapolis in September.
"This effort is a way to re-sensitize," Mr. Ellison added. "Some of this conversation has been so callous. 'Our rights, our rights, our rights.' Well, what about the suffering of our colleagues?"
Ms. McCarthy of New York has invited the chief of police from Malverne, N.Y., whose uncle, James Gorycki, was killed in the same shooting spree that claimed her husband.
Representative David N. Cicilline, Rhode Island's other House member, liked the idea so much that he had to tell his original State of the Union guest, the mayor of Central Falls, R.I., that he was sorry but that the invitation was going to someone else. Cleora Francis-O'Connor, whose son was 17 when he was shot and killed in South Providence, will attend instead.
Representative Elizabeth Esty, whose district includes Newtown, Conn., has invited someone closely linked to the tragedy at Sandy Hook Elementary School, where a gunman took the lives of 26 children and school employees in December.
Mr. Langevin's guest will be Jim Tyrell, whose sister was fatally shot in a robbery at a market in Providence.
The special wheelchair Mr. Langevin pilots, which was designed by the same inventor who created the Segway, allows him to raise himself up to about 5 feet tall so he can meet people at eye level, a useful position when your business is politics.
When he makes his case to colleagues on gun issues, his appeal is simple and unemotional. "My accident happened in what should have been one of the safest places to be: in a police station, at the hands of trained police officers," he often says. "So more guns are not the answer."
This article originally appeared in The New York Times.