Instantly acclaimed as one of the most important documentaries of the year, Ava DuVernay’s film about the mass incarceration of black men, “13th,” wowed audiences at the New York Film Festival and looks like a leading Oscar contender as it premieres in theaters and on Netflix on Friday.

Disappointingly, given the importance of the underlying issues, the film is a morass of distortions, half-truths, calculated omissions, absurd hyperbole and outright falsehoods. Equating Donald Trump supporters with Deep South lynch mobs isn’t even its most outlandish tactic.

DuVernay, the director of “Selma,” begins the film with a much-discussed but irrelevant statistic: The US, home to 5 percent of the world’s population, is also home to (nearly) 25 percent of the world’s prisoners.

Anyone who has ever thought about this imbalance, which tends to get trotted out in campaign seasons, will quickly understand the reason why: The US has a lot more crime than other countries.

If you think judges should sentence criminals based not on what they’ve been convicted of, but based on international incarceration disparities, fine. Let’s start with your neighborhood. Go ahead, lean on your local judges to let murderers and rapists off with a warning. It’s all for the noble cause of leveling out our incarceration rate, right?

DuVernay constructs her film around the fatuous notion that the 13th Amendment, which outlawed slavery, was deliberately constructed with a loophole that was meant to continue the mass enslavement of black people using indirect means.

The “loophole”? Convicted criminals can still be deprived of liberty. But this isn’t a loophole, it’s just a restatement of common sense. The US, like every other country on Earth, can lock you up if you are convicted of a crime. If this were so controversial, why has no one thought to be outraged about it before?

Viewers (such as film critics) who don’t pay especially close attention to the news pages are likely to be suckered by the misinformation in the movie. No, Woodrow Wilson didn’t say “The Birth of a Nation” was “history written with lightning.” No, Trayvon Martin didn’t die because of Florida’s “Stand Your Ground” law, which wasn’t even cited by George Zimmerman’s defenders. Martin died because Zimmerman exercised self-defense after Martin jumped on Zimmerman, punched him in the nose and pounded his head into the pavement. Zimmerman had injuries that backed up his story.

No, Walmart didn’t back the American Legislative Executive Council because it was fantasizing about people buying more Walmart guns to defend themselves under Stand Your Ground. (Walmart hasn’t even sold handguns since 1993; long guns are so infrequently used in homicides that more people die of wounds sustained from kicking and punching.)

As for the movie’s contention that John Ehrlichman, a key aide to President Richard Nixon, spilled the beans on racist drug policies when he allegedly said that Nixon cracked down on marijuana because he wanted to lock up hippies, and heroin because he wanted to lock up blacks — let’s look at the facts.

Ehrlichman allegedly gave this juicy quote to lefty journalist Dan Baum in 1994. Baum, who was writing a book on the drug wars that he published two years later, didn’t use the quote then. He didn’t tell anyone about the quote during the remainder of Ehrlichman’s life, which ended in 1999. Not until 2012 did Baum suddenly remember he was sitting on the quote of the century when it came to drug policy, and finally published it.

Do you really believe a journalist would sit on a bombshell quote like that for 18 years?

“13th,” which, especially in its final minutes, is unabashedly designed to motivate left-wing voters to get them to the polls, is purposefully vague during a strange tangent about Black Panthers and other Woodstock-era radicals. It avoids going into detail about, for instance, Assata Shakur, a convicted cop-killer who broke out of prison and fled to Cuba, who is portrayed as a hero here.

Van Jones, the ex-communist and 9/11 truther who appears repeatedly in the film as an expert witness, tells us that an entire generation of leaders was put in prison or forced to leave the country. “Leaders”? Tell that to all of the shooting and bombing victims of 1960s radicals. If your goal is to decrease the black prison population, extolling violent 1960s revolutionaries is a strange way to go about it.

Normalizing and even sentimentalizing left-wing 1960s extremists has become the new normal, however. Weren’t the Black Panther uniforms cool? As recently as a decade ago, you’d have had to visit a college campus to encounter such gullibility.

Yet the film saves the worst for last, closing with the shocking contention that blacks have made so little progress in the last 50 years that we’re still living in the Jim Crow era under a different name. This is an insult to the Civil Rights-era heroes who moved mountains in the cause of liberty and justice. It’s an insult to Martin Luther King Jr., the hero of DuVernay’s last film, “Selma.”