The number of police officers killed in crimes dropped last year, a development that could provide a counterweight to arguments that a backlash against American cops has led to them being targeted for violence.
Forty-one officers died "feloniously" — as the result of criminal acts — in 2015, down from 51 in 2014, the FBI announced Monday.
The decline reversed a dramatic one-year spike that fueled speculation that cops had come under siege amid a wave of anti-cop sentiment following a string of high-profile fatal police shootings.
With the new numbers, that spike looks more like an anomaly.
Only twice in nearly 60 years have the number of police officers killed in criminal acts fallen lower than the 41 in 2015, according to FBI data. The last time was 2013, the year that preceded the recent spike, when the deaths hit a record low of 27. In 1961, there were 37.
FBI Director James Comey said in a statement Monday that any number of officer deaths was too many, and described the "heartbreaking" phone calls he makes to families and police chiefs who have lost someone.
Comey, who in other remarks has raised concerns about the impact of anti-cop sentiment on the crime rate, acknowledged in his statement that many officers remain concerned that they "aren't viewed with the respect and gratitude that we'd expect, but instead of suspicion and mistrust."
He said that needed to change.
"All of us in law enforcement have to continue to reach out to the communities we serve so that folks can understand better the difficult and often frightening work that we do to keep them safe," Comey said. "At the same time, we have to continue to listen to their concerns and work with them to build and improve the relationships that are at the center of our success."
The National Law Enforcement Officers Memorial Fund, which tracks officer deaths differently than the FBI, said the annual numbers were actually higher when taking into account corrections officers and cops who work for agencies that don't share their data with the federal government. The organization counted 55 felonious police killings in 2015, a decline from 62 in 2014, spokesman Steve Groeninger said.
Groeninger added that the group's data showed that killings have been below historical averages in recent years.
He acknowledged that it was difficult to connect the data to broader trends, but said there were still many instances of cops being targeted. Earlier this year, his organization raised alarms over a spate of ambush killings that included Prince William County Police Officer Ashley Guindon, shot to death on her first day of work while responding to a domestic violence call.
This undated photo provided by the Prince William County Police shows Officer Ashley Guindon. Lawyers for an Army Staff Sgt. Ronald Hamilton accused of fatally shooting a police officer working her first shift are fighting prosecutors' efforts to bring the sergeant's 11-year-old son in front of a grand jury, Thursday, May 5.
President Obama mentioned Guindon at an awards ceremony marking the start of Police Week, saying officers' deaths should remind Americans of the difficulty of their jobs, and that they deserve the country's support, especially as it debates ways to reform the criminal justice system.
"Our nation has a responsibility to support those who serve and protect us and keep our streets safe," Obama said. "We can show our respect by listening to you, learning from you, giving you the resources you need to do the jobs."
David Harris, a law professor at the University of Pittsburgh who researches police behavior, said the long-term decline in killings of police officers is likely due to improvements in training and equipment and advances in the treatment of traumatic injuries. It also may be linked to historic drops in violent crime. But he stressed that it was nearly impossible to get more specific than that.
Harris said that he expected the killings of officers to continue to decline as more departments embrace training that emphasizes deescalating potentially violent confrontations.
Some officers have dismissed that prediction as overly cautious. But Harris called it "a welcome trend."
This story originally appeared on NBCNews.com.