Nobel Prize-winning novelist Toni Morrison says she wants to see an officer shoot an unarmed white teenager in the back before agreeing that the “conversation about race” is over, but she almost certainly already has received her wish.

“This is the conversation. I want to see a cop shoot a white unarmed teenager in the back,” said Ms. Morrison, who also has won the Pulitzer Prize for her work, which includes the bestsellers “Beloved” and “Song of Solomon.” “And I want to see a white man convicted for raping a black woman. Then when you ask me, ‘Is it over?’, I will say yes.”

Her comments reflect a widespread view that blacks are routinely targeted by law enforcement while whites shot by police are a rarity. Outrage has surged in recent weeks over the high-profile deaths of black men at the hands of police, notably 50-year-old Walter Scott of South Carolina, who was shot in the back and killed April 4 as he tried to run away from an officer after a traffic stop.

The officer who shot him, Michael Slager, has been charged with murder, and the Justice Department is investigating the case for civil rights violations. Department officials announced Tuesday that they have opened a federal probe into the death of Freddie Gray, 25, who died Sunday from injuries sustained while in Baltimore police custody.

More White People Shot by Police Than Blacks

An analysis released last week shows that more white people died at the hands of law enforcement than those of any other race in the last two years, even as the Justice Department, social-justice groups and media coverage focus on black victims of police force.

“People keep saying, ‘We need to have a conversation about race,’” Ms. Morrison told the (U.K.) Telegraph in an April 19 interview.

Nearly a thousand times this year, an American police officer has shot and killed a civilian.

When the people hired to protect their communities end up killing someone, they can be called heroes or criminals — a judgment that has never come more quickly or searingly than in this era of viral video, body cameras and dash cams. A single bullet fired at the adrenaline-charged apex of a chase can end a life, wreck a career, spark a riot, spike racial tensions and alter the politics of the nation.

In a year-long study, The Washington Post found that the kind of incidents that have ignited protests in many U.S. communities — most often, white police officers killing unarmed black men — represent less than 4 percent of fatal police shootings. Meanwhile, The Post found that the great majority of people who died at the hands of the police fit at least one of three categories: they were wielding weapons, they were suicidal or mentally troubled, or they ran when officers told them to halt.

The Post sought to compile a record of every fatal police shooting in the nation in 2015, something no government agency had done. The project began after a police officer shot and killed Michael Brown in Ferguson, Mo., in August 2014, provoking several nights of fiery riots, weeks of protests and a national reckoning with the nexus of race, crime and police use of force.

Race remains the most volatile flash point in any accounting of police shootings. Although black men make up only 6 percent of the U.S. population, they account for 40 percent of the unarmed men shot to death by police this year, The Post’s database shows. In the majority of cases in which police shot and killed a person who had attacked someone with a weapon or brandished a gun, the person who was shot was white. But a hugely disproportionate number — 3 in 5 — of those killed after exhibiting less threatening behavior were black or Hispanic.