The comedian Roseanne Barr resurrected one of the oldest and most profoundly racist slanders in U.S. history when she referred to Valerie Jarrett, an African-American woman who served as an adviser to President Barack Obama, as the offspring of an ape.

This depiction — promoted by slave traders, historians and practitioners of “scientific” racism — was used to justify slavery, lynching and the creation of the Jim Crow state. It made the leap to the silver screen in deeply noxious films like “The Birth of a Nation” and haunted U.S. popular culture well into the 20th century.

The toxically racist ape characterization has been pushed to the margins of the public square. Nevertheless, a growing body of research shows that it has maintained a pernicious grip on the U.S. imagination. It is especially problematic in the criminal justice system, where subhuman treatment of African-Americans remains strikingly visible.

That message comes through powerfully in research by several social scientists, but particularly in the work of the Stanford University psychologist Jennifer Eberhardt and Phillip Atiba Goff, president of the Center for Policing Equity at John Jay College in New York. In six studies published with collaborators a decade ago, Goff and Eberhardt found that even younger study participants who were born since the civil rights revolution and claimed to know nothing of the ape caricature of blackness were swayed by it when making judgments about black people. In one study, white male undergraduates who were subliminally exposed to words associated with apes — for example, “chimp” or “gorilla” — were more likely to condone the beating of those in police custody when they thought that the suspect was black.

In another study, the authors analyzed death penalty cases covered in The Philadelphia Inquirer between 1979 and 1999. They found that black defendants convicted of capital crimes were four times more likely than whites convicted of capital crimes to be described with labels associated with apes, such as “savage,” “brute” or “beast.” The researchers also discovered that defendants who were implicitly portrayed as more apelike in the newspaper were more likely to be executed by the state.

This process of dehumanization often leads Americans to view African-American men as larger and more fearsome than they are. This pattern of misperception is troubling. Police officers are often exonerated for killing civilians on the premise that they fired their weapons out of fear for their lives. This issue famously came up in the 2014 killing of Dontre Hamilton, an unarmed black man in Milwaukee who was shot 14 times by Officer Christopher Manney. Manney later portrayed Hamilton as hulking and muscular, saying he feared being “overpowered.” An autopsy showed that Hamilton was actually of modest build — 5 feet, 7 inches tall and 169 pounds.

The tragedy of 12-year-old Tamir Rice, who was killed by a Cleveland police officer in 2014 while playing with a toy gun, fits this pattern. An officer at the scene described him as being 20 years old. Black children are often seen as significantly older and more menacing than they actually are. And, research suggests, the automatic presumption of threat provoked by a black face applies even the when the face belongs to a 5-year-old.

Goff and his colleagues published a striking set of studies the year Tamir was killed. They found that when a group of mainly white college students were shown photographs of white, black and Latino children, they overestimated the ages of black children by an average of 4.5 years. In other words, they perceived 13-year-old boys as adult men — and viewed black children as more culpable for crimes.

The ape caricature plays a role here, too. The more participants associated black people with apes, the authors showed, the greater the discrepancy between their guesses of the ages of black children and their actual ages — and the more severely the participants judged the children’s culpability. A related analysis of police personnel records determined that officers who associated blacks with apes were more likely to have used force against a black child in custody.

The backlash that forced ABC to cancel Barr’s television series reflects a distaste for passe, plainly stated racism in a society that likes to see itself as having put bigotry behind it. Nevertheless, centuries of institutional racism — and the dehumanization of black people upon which it relied — have left an indelible imprint on how Americans process blackness.

The notion that the country might somehow move past this deeply complex, historically layered issue by assuming an attitude of “color blindness” is naive. The only real hope of doing that is to openly confront and talk about the powerful, but submerged, forms of discrimination that have long since supplanted the undisguised version.

— Brent Staples is an editorial writer for The New York Times.