Police nationwide shot and killed 492 people in the first six months of this year, a number nearly identical to the count for the same period in each of the prior two years.
Fatal shootings by police in 2017 have so closely tracked last year's numbers that on June 16, the tally was the same. While the number of unarmed people killed by police dropped slightly, the overall pace for 2017 through Friday was on track to approach 1,000 killed for a third year in row.
The Washington Post began tracking all fatal shootings by on-duty police in 2015 after the 2014 shooting in Ferguson, Mo., of Michael Brown, who was unarmed and had an altercation with the officer who shot him. The ongoing Post project has documented twice as many shootings by police in 2015 and 2016 as ever recorded in a single year by the FBI's tracking of such shootings, a pattern that is emerging again in 2017.
Since Brown's killing in Ferguson, other fatal shootings by police, many captured on video, have fueled protests and calls for change. Some police chiefs have taken steps in their departments to reduce the number of fatal encounters, yet the overall numbers remain unchanged.
[IN-DEPTH: Investigation into police shootings in Arkansas]
Academics who study shootings give weight to the Post's accounting.
"These numbers show us that officer-involved shootings are constant over time," said Geoffrey Alpert, a criminologist at the University of South Carolina who has studied police use of force. "Some places go up, some go down, but its averaging out."
As in previous years, the data gathered by the Post showed that police most frequently killed white men and boys who were armed with guns or other kinds of weapons. One in four people killed this year were mentally ill, and police have continued to shoot and kill a disproportionately large number of black men and boys, who account for nearly a quarter of the deaths yet are only 6 percent of the nation's population.
This year, fatal shootings of unarmed people have declined, continuing a trend over the past two years. In the first six months of this year, 27 unarmed people had been fatally shot, compared with 34 for the same period in 2016 and 50 in the first six months of 2015.
Black men and boys continued to represent a disproportionately large share of unarmed people killed, although their share has dropped slightly: from 32 percent of all unarmed killings during the first six months of last year to 26 percent so far this year.
[Read about recent fatal shootings by police across the country.]
Mental illness has remained a factor in fatal police shootings, as a quarter of those killed were struggling with a mental-health issue.
Chuck Wexler, executive director of the Police Executive Research Forum, which develops training programs and advises police chiefs around the country on policy, said some fatal shootings can be eliminated.
"We know we can make a difference in cases where the person is mentally ill and in cases where someone is not armed with a gun," Wexler said.
The study by the Post has found that about 8 percent of the nation's police departments have had at least one fatal shooting since 2015. Of those, most had only one.
The pace at which officers have been killed in the line of duty has held steady over the past two years.
According to the FBI, 21 police officers were killed from January to Thursday, two fewer than in the same period last year. The 2016 year ended with 66 officers killed, not including accidental deaths. Since January 2015, according to the FBI, 128 police officers have been killed in the line of duty.
There is no comprehensive government data source that tracks fatal shootings by police officers. The Post database relies on local news coverage, public records and social-media reports to identify fatal shootings by police.
The FBI gathers information on fatal police shootings, but that program is based on voluntary reporting by police agencies and covers only cases in which police fatally shoot someone who is committing a felony.
The Post's project, and a similar counting effort by the Guardian newspaper in 2015, prompted now-fired FBI director James Comey to call his own agency's system "embarrassing and ridiculous." In October 2016, the Justice Department announced that it would move forward with plans to collect better data about officer-involved shootings.
The FBI said it would launch on Saturday a pilot study of that data collection program that will gather a broad range of information on use of force from about 50 local and federal law enforcement agencies. The FBI said it intends to begin nationwide collection of the data in 2018.
"When a police officer takes a life, that's a significant event," said Darrel Stephens, the executive director of the Major Cities Chiefs Association. The group, which includes 80 police chiefs and sheriffs, helped advise the FBI on the pilot program. "We should know on a national basis how many times that happens and under what circumstances."
Information for this article was contributed by Ted Mellnik, Steven Rich, Jerrel Floyd and Catherine York of The Washington Post.
A Section on 07/02/2017