Jennifer Mascia figures she covered 50,000 Americans' firearm-related deaths while writing for The New York Times' Gun Report blog from January 2013 until June 2014. America Tonight

Mascia expected gang- and drug-related violence would be the leading cause of gun deaths. Instead, she was surprised by the number of killings in which a passing flare-up of emotion – anger, jealousy, fear, sadness – became the final chapter in someone’s life by adding in the deadly efficiency of a gun.

“Until the bullet leaves the chamber, they don't understand the repercussions,” Mascia said. “But it ends up being catastrophic, and that is not understood until you have a bleeding person in front of you.”

Mascia says combing through tragedy after tragedy numbed her to the violence, but every so often a story stood out.

“The most disturbing story I ever covered in the Gun Report was a 79-year-old man who had been diagnosed with cancer,” she said. “And his wife and her sister were in the house and he was bedridden, depressed, and he had a gun and he was going to kill himself. And his wife, who was also 79, walked into the room, and her sister heard her through the door. [The wife] was begging him, ‘Please don’t do this. I love you.’ And he shot and he killed her.”

The man turned the gun on himself, but it misfired. He died in a hospital three days later.

But the ubiquity of gun violence in America didn’t truly become personal for Mascia until Nov. 13, 2013. That's the day she pulled up the Times' homepage and discovered that Ali Eskandarian, a musician she knew, had been shot and killed in Brooklyn, along with two members of the Iranian-American band The Yellow Dogs.

“He was in his living room and a shot came through the window,” Mascia said. “Never in a million years did I think that he would be a victim of gun violence. Never would have crossed my mind.”