Editor's note:This column contains a racial epithet.

One day in the 1930s, a very young Martin Luther King Jr. was sitting in the passenger seat of his father's car when his dad accidentally ran a stop sign on a Georgia street.

"A policeman pulled up to the car and said: 'All right, boy, pull over and let me see your license,' " King remembered in an essay years later. "My father replied indignantly, 'I'm no boy.' Then, pointing to me, 'This is a boy. I am a man, and until you call me one, I will not listen to you.' "

The officer was so flummoxed that he quickly wrote out the traffic ticket and hurried away.

Some years later, when King was a civil rights activist writing from a Birmingham, Ala., jail cell, he would point to that word — boy — as one of Jim Crow's ritual humiliations, braided into the racial etiquette of the post-slavery South. It was yet another way — like withholding simple courtesies like honorifics — that white people weaponized language to remind black folks of their place.

The slight was unmistakable. If manhood was the precondition for the actualization of rights, "boy" denied that status even to other men who might lay claim to it. In a region steeped in manners and terms of deference, no black man was ever old enough to age out of "boy"; no white person was ever too young to toss it in his direction.

"Boy" shows up again and again, if implicitly, in the language of black resistance to white oppression. "Think about those video reels and the black-and-white photos of black men during the civil rights marches with sandwich boards or placards saying 'I Am A Man'," the Bucknell linguist Hiram Smith said. There's an old urban legend, Smith added, in which black Jazz Age musicians began using "man" as a term of affection — as in, "What's happening, man?" — as a rebuke to "boy."

So was "boy" a slur? That was a central question of a sprawling employment discrimination suit in Alabama, which began in 1996 and didn't end until 2016. In that case, a black plant worker argued that his white supervisor had called him "boy" as he barked orders at him. For two decades, a series of juries and judges — and eventually the Supreme Court of the United States — repeatedly disagreed over what the supervisor meant when he said it. At one point, some of Martin Luther King's contemporaries in the civil rights movement filed an amicus brief on the plaintiff's behalf, hoping to make the point clear: "If not a proxy for 'nigger,' it is at the very least a close cousin." Unlike that close cousin, of course, "boy" has usages that are not irradiated by race, which provides a lot of plausible deniability for the times when it most certainly is. (The plaintiff eventually won.)

But the echoes of that more sinister denotation remain. Just this past spring, an organization of black journalists urged The Associated Press to adopt new guidelines on "boy, saying that it felt the term was being used too cavalierly in news stories, especially ones about police violence against black males.

Swirling around that legitimate concern about applying "boy" to describe fully grown black men is a growing body of evidence that lays out the ways that actual black boys have been gerrymandered out of the very notion of boyhood. If childhood is a time of innocence that warrants protection, then that stage of life ends much earlier and more abruptly for black boys.

Research backs this up. In a study from 2014, psychologists asked police officers to look at photographs of boys between the ages of 10 and 17. The officers were told, at random, that the boys in the pictures were suspected of either a petty crime or a felony. Then the participants were asked to guess the ages of the boys in the photos. The officers consistently perceived black boys as older than they were — by an average of 4.5 years.

Those black boys were seen as legal adults when they were a little over 13 years old. (In the same study, the officers saw whiteboys in the photographs as younger than they actually were.)

This aging up of black boys has serious consequences, the study's authors said, including making it more likely that black boys would have force used on them in police encounters.

"Our research found that black boys can be seen as responsible for their actions at an age when white boys still benefit from the assumption that children are essentially innocent," one of the researchers wrote.

Those findings line up with other studies that have found that black boys are more likely to be tried by prosecutors as adults in criminal proceedings and more likely to be sent to adult prisons. Even in early childhood, black boys face tougher consequences for for their actions than do white boys of the same age. The Yale researcher Walter Gilliam wrote that being either "big, black or boy" was the biggest predictor of whether a child was suspended or expelled from preschool.

White boys — particularly those who are better-off — enjoy that presumption of childhood innocence until much later in life, and it's a distinction that has apparently always been baked into the very notion of adolescence. Back in the 1890s, G. Stanley Hall, the first president of the American Psychological Association, championed the then-novel idea of a distinct developmental stage between childhood and adulthood, according to Ashwini Tambe, a professor of women's studies at the University of Maryland. "He imagined it as a stage of storm and stress and turbulence and sexual experimentation," she said.

But Tambe noted that Hall and his contemporaries imagined this phase of necessary recklessness for those like themselves: male, white, educated and affluent. In his seminal 1904 book, Adolescence, Hall wrote that "[a] period of semicriminality is normal for all healthy boys ... those whose surroundings are bad will continue it, but others will grow away from it as they approach maturity." Practically speaking, this period of constructive delinquency was not on the table for poor children of all races who couldn't put off adult responsibility because they needed to work or for white girls of similar privilege, as they were expected to be better-behaved.

And so: "Boys will be boys;" "Saturdays are for the boys;" "the old boys' club." Brock Turner. Ethan Couch. Cameron Terrell.

And, of course, the recent debate over the newest Supreme Court justice. During Brett Kavanaugh's confirmation hearings, in which he faced accusations that he committed a sexual assault in high school, he leaned into the particulars of his prep school life — barbells, basketball, beer, bro'ing out — as if the mere fact of them was exculpatory.

(Try to imagine a black man accused of sexual violence trying to convince people that his routine underage drinking should get him off the hook.)

And in their defenses of him, many of Kavanaugh's supporters quite literally imagined their own male children as future Brett Kavanaughs — promising, upstanding men who might one day have their good names ruined by scheming women and too-credulous presumptions about their guilt.

It's a defense not readily available to everyone. Kavanaugh, after all, was nominated by a man who once took out newspaper ads that called for the death penalty for five boys of color accused of a brutal rape. The boys were 14, 15 or 16 years old at the time of their arrests and tried as adults; the newspapers covering the story broke from convention by naming the accused minors and prominently running their photos. When they were exonerated by DNA evidence decades later, Donald Trump continued to argue that the five now-grown men should never have been cleared. "These young men do not exactly have the pasts of angels," Trump wrote. Their pre-prison pasts, though, were essentially their childhoods.

Whether a black male is treated as a "boy" or a "man" has so often depended on which of those categories might invite the most consequence. White men of means, though, are seldom too old to have aged out of the benefit of the doubt.

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