Heslin's 6-year-old son, Jesse, was killed in the Sandy Hook massacre in Newtown, and Heslin was here to testify in favor of Sen. Dianne Feinstein's proposed assault weapons ban. The audience in the jam-packed Senate hearing room had earlier been vocal but was utterly hushed as Heslin tearfully described his final moments with Jesse Lewis on the morning of Dec. 14.
"It was 9:04 when I dropped Jesse off ... Jesse gave me a hug and a kiss and said, 'Goodbye. I love you.' He stopped and he said, 'I love Mom, too.' That was the last I saw of Jesse as he ducked around the corner."
Many Newtown residents were in the audience as Heslin and a parade of other witnesses presented their views on the latest assault-weapons ban that Feinstein, D-Calif., has proposed -- a bill that is viewed as a longshot to become law.
Heslin said, "I waited in that (Sandy Hook) firehouse until 1 in the morning. . . till I knew Jesse was confirmed dead.
"No person should have to go through what myself or any of the other victims' families had to deal with, and what the town of Newtown had to go through," he said. "My son was brutally murdered."
Feinstein, starting by displaying the pictures of all 26 Newtown victims, said, "That horrific event shocked our nation to its roots. And these pictures ... brought tears to the eyes of millions of Americans.
"We are holding today's hearing because sadly Newtown was not an anomaly," she said. "The one common thread running through these mass shootings in recent years, from Aurora, Colorado, to Tucson, Arizona, to Blacksburg, Virginia, is that the gunman used a military-style semiautomatic assault weapon or a large-capacity ammunition magazine to commit unspeakable terror."
Walsh and Flynn both advocated restrictions on automatic weapons, describing the carnage they had encountered as criminal-justice professionals. Walsh mentioned both Columbine and Aurora, and Flynn made reference to police being outgunned and American cities facing "slow-motion mass murder every single year."
Republicans on the Senate Judiciary Committee painted a different picture, repeatedly raising the arguments that existing gun laws are not well-enforced, and that an assault-weapons ban would infringe on the rights of law-abiding citizens.
Texas Republican Sens. John Cornyn and Ted Cruz, who have been conservative outliers on a number of issues in the opening days of this Congress, voiced their opposition to the proposed assault-weapons ban but were measured in front of the Newtown victims.
Cruz offered condolences to gun-violence victims in a statement: "I'd like to express the deepest sympathy that law enforcement was unable to prevent the horrific crimes you suffered."
As for an assault weapons ban, Cornyn said, "Call me skeptical -- because criminals will continue to get weapons. I want to make sure that if we're going to act, that we act responsibly and don't just pass some additional laws that won't have an impact."
Sen. Richard Blumenthal. D-Conn., said, "The Ph.Ds and the lawyers may debate the numbers, but the simple blunt fact is that some or all of those 20 beautiful children and six great educators would be alive today if assault weapons had been banned, along with high-capacity magazines."
Begg, too, was emotional. A parent of three Newtown students, he said, "My goal is to convince you, senators ... that banning assault rifles will make a difference."
He added, "What galls me is those who say let's really focus on mental health are the same ones who are saying, 'Well, we need to have a conservative approach and balance the budget and cut programs.' Well, what are the first programs that are cut? Mental health!
"People say that the overall number of assault weapon deaths is relatively small, but you know what? Please don't tell that to the people of Tucson or Aurora or Columbine or Virginia Tech, and don't tell that to the people in Newtown!"