Representative Jamie Raskin (D., Md.) claimed on the floor of the House of Representatives that there had been nearly 400 shootings where 4 or more people were killed in the United States in 2017, an estimate that was off by more than 350.

“Since January, we’ve had 397 gun massacres in America, defined as a slaying of 4 people or more,” Raskin said during a debate over national gun-carry reciprocity legislation.

Though Raskin did not cite a source for the numbers he used on the House floor, his count does not match any publicly available review of shootings in the United States. A Washington Free Beacon review of the gun-control advocacy group Mass Shooting Tracker’s statistics shows there have been 40 shootings where 4 or more people were killed between January 1, 2017, and December 4, 2017. That’s 357 fewer shootings than the congressman identified.

The Mass Shooting Tracker’s definition of mass shooting, where 4 or more people are injured but not necessarily killed in the shooting, is closer to Rep. Raskin’s estimate. The media have pushed the activist group’s numbers despite their open bias and their diversion from the FBI definition of mass murder, which sets the standard at 3 or more killed simultaneously. The number of mass shootings increases dramatically under the definition favored by gun-control activists.

The group of activists behind the Mass Shooting Tracker have been open about their political leanings. “We make no secret of the fact that we are a strongly opinionated group of people,” a note on the group’s website said. “Most of us support gun control. However, we believe that the best way to make our case is to present facts as objectively as possible.”