Hillary Clinton repeated her incessant lie Monday that the criminal-justice system is infected with “systemic racism.”

Race “determines” how people are “treated in the criminal justice system,” she said. Blacks are “more likely [than whites] to be arrested, charged, convicted and incarcerated” for “doing the same thing.”

Such a falsehood, should Clinton act on it as president, would result not just in misguided policies but in the continued delegitimation of the criminal-justice system. That delegitimation, with its attendant hostility and aggression toward police, has produced nearly the largest one-year increase in homicides in half a century.

Criminologists have tried for decades to prove that the overrepresentation of blacks in prison is due to criminal-justice racism. They’ve always come up short — forced to the same conclusion as Michael Tonry in his book, “Malign Neglect: “Racial differences in patterns of offending, not racial bias by police and other officials, are the principal reason that such greater proportions of blacks than whites are arrested, prosecuted, convicted and imprisoned.”

To say, as Clinton did, that blacks are more likely to be incarcerated for doing the same thing as whites ignores the relevance of a defendant’s criminal history in determining his sentence, among other crucial sentencing factors.

Clinton also complained that “too many young African-American and Latino men end . . . up in jail for non-violent offenses.” In fact, the majority of prisoners in the US are serving time for violent felonies.

The enforcement of low-level public-order offenses in New York City under Mayors Rudy Giuliani and Michael Bloomberg actually lowered New York’s prison population by intervening in criminal behavior early, before it ripened into a serious felony.

Clinton may think low-level public-order enforcement (a k a “broken windows” policing) is racist, but law-abiding residents of high-crime communities beg the police to enforce public-order laws because they know that out of street disorder erupts gun violence and other predation.

Clinton claimed “stop-and-frisk was found to be unconstitutional.” In fact, the US Supreme Court put its imprimatur on the practice, which remains a lawful and essential police tactic.

Federal Judge Shira Scheindlin’s ruling that the NYPD’s practice of stops was racially biased applied only to the NYPD — and likely would’ve been reversed, had Mayor de Blasio not dropped the appeal.

Scheindlin used a population benchmark for measuring the lawfulness of police actions: If police stops didn’t match population ratios, they were unconstitutional. Yet that ignores the massive disparities in criminal offending.

Blacks, though 23 percent of the city’s population, commit over three-quarters of all shootings. Add in Hispanic shootings, and you account for 98 percent of all shootings in New York. Whites, 34 percent of the city’s population, commit less than 2 percent of all shootings.

Such disparities mean that virtually every time the police are called out on a gun run — i.e., someone has been shot — they’re called to minority neighborhoods on behalf of minority victims, and, if any witness is cooperating, being given a description of a minority suspect.

The reality of crime, not phantom racism, determines the incidence of police activity.

Clinton claimed that stop-and-frisk was “ineffective.” Felony crime in the city dropped 85 percent from the early ’90s to the mid-2010s; more than 10,000 minority males were spared the violent death they would’ve experienced had homicides remained at early-’90s levels.

Stop-and-frisk was a crucial part of that crime drop; it’s hard to imagine anything more effective than New York’s proactive policing revolution.

Thanks to the Scheindlin-induced drop in stops, homicides and shootings in the city rose 20 percent in the first half of 2015. Then-Commissioner Bill Bratton responded with a massive deployment of manpower to high-crime corners; officers used “command presence” — i.e., their mere presence on the street — to deter crime.

This rollout of manpower quelled the shooting spike; the city ended 2015 with a 6 percent homicide increase. But other departments lack the personnel to make up for a drop in proactive policing.

Donald Trump is right to warn about depolicing and what I have called the Ferguson Effect. “Right now, our police, in many cases, are afraid to do anything,” he said.

The result is a massive loss of black lives in places like Chicago and Baltimore. Law and order are breaking down in inner cities; officers are surrounded by hostile, jeering crowds when they get out of their squad cars to conduct an investigation. Resistance to arrest is up, increasing the chances of an officer’s own use of force. And race riots are returning to US cities.

The current mendacious narrative about policing and race has to change or we can expect to see further violent-crime increases and further racial violence. It’s clear, however, that Hillary Clinton will continue to enflame racial tensions through a set of lies about the criminal-justice system.

Heather Mac Donald is the author of the bestselling “The War on Cops.”

From city-journal.org.