WASHINGTON — Years before the high-profile deaths of Trayvon Martin, Michael Brown and Freddie Gray, more than half of African-American millennials indicated they, or someone they knew, had been victimized by violence or harassment from law enforcement, a new report says.

The information, from the “Black Millennials in America” report issued by the Black Youth Project at the Study of Race, Politics and Culture at the University of Chicago, reflects starkly different attitudes among black, Latino, Asian and white millennials when it comes to policing, guns and the legal system in the United States. Researchers, who have surveyed millennials several times during the past decade, point out that the disparities existed well before the “Black Lives Matter” movement began.

In the 2009 Mobilization and Change Survey, 54.4 percent of black millennials answered yes to the question “Have you or anyone you know experienced harassment or violence at the hands of the police?” Almost one-third of whites, 1 in 4 Latinos and 28 percent of Asian-Americans surveyed said yes to the same question.

This study, released to The Associated Press on Wednesday, comes as the United States grapples with concerns over policing in minority communities following the deaths of Martin, 17, in Florida three years ago, Brown, 18, in Ferguson, Missouri, last year and Gray, 25, in Baltimore earlier this year. Their deaths, as well as those of other black men and women, have inspired nationwide protests under the “Black Lives Matter” and “Say Her Name” monikers.

But even while being the wellspring of those movements, a clear majority of black millennials — 71 percent — said in that same survey they believe police in their neighborhood were “there to protect you.” Eighty-five percent of whites, 76 percent of Hispanics and 89 percent of Asians also said police were in their neighborhood to protect them.