When federal authorities said Alice Boland threatened to kill the president, she avoided a felony conviction because she claimed insanity — precisely the reason she managed to buy a gun seven years later.

It’s an irony that U.S. Sen. Lindsey Graham pointed to Wednesday as a flaw in gun laws — it’s an “outrage,” he said — that allowed the 28-year-old from Beaufort to legally obtain a pistol and use it to threaten Ashley Hall school officials in downtown Charleston.

During remarks in Washington, the South Carolina senator echoed what his Republican colleagues have repeated in the weeks since 26 people were slain at a Connecticut elementary school. He asked Democrats to focus on strengthening rules already on the books, but also called for firearms prohibitions against people who use claims of mental illness to skirt criminal convictions.

Boland’s plea of not guilty by reason of insanity, he said, should have raised flags when she bought the .22-caliber Taurus PT22. Graham said he plans to draft legislation to ensure that “people like her” can’t buy a gun in a store.

“To me, this is Exhibit A of a broken system,” Graham said. “How can it be that the background check would allow her to buy a gun?

“Alice Boland getting a gun is a failure of the current system.”

As Boland’s history of mental illness has become known since Feb. 4, the Ashley Hall episode has garnered attention in gun-control debates nationwide. The emerging details also have prodded those affected by the incident to speak out.

This week, 56 parents of students at the all-girls private school signed a letter sent to Graham and 11 other state and federal legislators.

The two-page letter described the parents as bipartisan voters uninterested in dismantling the Second Amendment.

Rather, it bemoaned the state for not submitting mental health disqualifiers to the National Instant Criminal Background Check System.

“Please do something to prevent the Alice Bolands of the world from buying guns in South Carolina,” Michel Faliero wrote on the parents’ behalf.

Faliero said Wednesday that the parents were “encouraged” by Graham’s comments. She expressed hope that legislation would require states to enter records of “potentially violent mentally ill people” into the national database.

As news of Boland’s case has spread, more lawmakers also have addressed it — though, in some cases, cursorily.

Gov. Nikki Haley’s spokesman last week said it exposed a need to further funding of mental health care.

Republican U.S. Sen. Tim Scott was restrained in his remarks this week during a visit to Medical University Hospital.

“If she purchased it legally, then she did,” he said. “I can’t tell you whether she should have or shouldn’t have been able to.”

Boland remains in jail.

She is accused of pointing a pistol at an Ashley Hall official and pulling the trigger. The weapon was loaded, but it didn’t fire because no cartridge was in the chamber. Boland thought it was defective.

The gun is equipped with a built-in locking mechanism, but it was not engaged at the time, police said. The gun was fully functional.

On Wednesday, Boland’s mother said “wow” when she learned that Graham had addressed her daughter’s case.

Dellann Boland said she has been instructed by her daughter’s public defender not to speak publicly.

In an interview with The Post and Courier this week, the mother described her family’s decade-long struggle to find and pay for proper care.

“I’m not making any comments about this right now,” she said Wednesday.

Her daughter’s booking photo was enlarged and emblazoned on one of the two posters flanking Graham as he spoke.

The boards highlighted Boland’s federal court history since 2005, when the Secret Service said she repeatedly threatened to shoot President George W. Bush, and her forced treatment for schizophrenia.

Graham repeated many of Boland’s alleged comments.

“One bullet in the hands of Ms. Boland is one too many,” Graham said.

“I intend to introduce legislation so that the Alice Bolands of the future do not pass a background check.”

Part of his proposal, he said, will include provisions to prosecute people who use deception in trying to buy a gun. He showed a poster illustrating that only 44 of the 80,000 people who failed background checks in one year were prosecuted.

If someone doesn’t disclose a mental health history that prohibits a gun purchase, for example, that person would be prosecuted under Graham’s plan. It’s a felony to lie on the federal transaction questionnaire.

The senator referred to a plan that President Barack Obama mentioned in his State of the Union Address the night before as only a “marginal” threat to gun violence.

Obama concluded his speech with an emotional plea for a law that keeps firearms out of criminals’ hands by, in part, limiting private sales.

Graham asked the president to stop being a “cheerleader” for gun laws. He also mentioned that he owns an AR-15 rifle and enjoys Quentin Tarantino movies.

Reach Andrew Knapp at 937-5414 or twitter.com/offlede.