If the Bill de Blasio mayoral reign had a catch phrase, it would be: “Do as I say, not as I do.”

A few days ago, the New York Daily News exposed a new ­detail in the coverup of a traffic accident involving Hizzoner: “De Blasio’s NYPD SUV was cruising the wrong way with lights and sirens blaring when it got into a car crash, sparking a frantic coverup by his security detail.”

Despite state law to the contrary, no accident report was filed with the DMV. The new ­information that his car drove into oncoming traffic just underscored how the rules don’t apply to him.

It was particularly galling, coming from the mayor who ­implemented the Vision Zero initiative for safer streets. The website for the initiative is very serious about collisions. “This status quo is unacceptable,” it says. “The City of New York must no longer regard traffic crashes as mere ‘accidents,’ but rather as preventable incidents that can be systematically addressed.”

The website doesn’t mention why it’s OK for the mayor’s car to go the wrong way down a one-way street because he’s really, really important.

This pretense and fakery is standard in the de Blasio administration and the latest in a pattern suggesting there is one set of rules for him and his circle, another for us little people.

A different story this week highlighted another way the mayor and his friends get preferential treatment.

Cheryl Watson-Harris, a top deputy to Schools Chancellor Richard Carranza, was recently handed a seat for her daughter at the in-demand IS 187, the Christa McAuliffe School, one of the best middle schools in Brooklyn. This, while parents in District 15 scramble to deal with the new middle school process, which removed “screens” for middle schools, so that there are no “good” schools or “bad” schools, just bleh schools.

As Susan Edelman reported in The Post a few days ago, “the girl entered in the 8th grade, ­although the grade 6-8 school normally accepts only incoming 6th graders.” But what’s a little rule-bending for the elites in de Blasio’s circle?

All the wacky plans and schemes of the de Blasio administration, such as removing screens from a performing arts middle school in Sunset Park so it no longer matters whether a child has any particular talent in the arts? That’s for us little people. Watson-Harris’ youngest son “attends Mark Twain for the Gifted and Talented in Coney Island, a highly competitive and coveted school that chooses kids based on entrance exams and tryouts.”

One set of rules for me and another for thee has long been the mayor’s way. After all, his kids went to a mostly white, screened middle school in Park Slope. The mayor was gung-ho to end its elite status — once it didn’t personally affect him.

His son went on to Brooklyn Tech, one of the high schools that require the SHSAT exam that de Blasio wants to eliminate. His daughter went to Beacon High School, another one of those schools with the “screens” de Blasio claims to detest. Yet now anyone opposing the new changes gets called “racist” by Carranza.

Also this week, the mayor held a rally at Trump Tower. Talking over protesters who shouted “Worst mayor ever!” and “You suck!” de Blasio threatened Donald Trump by name and said “we will take your money” if Trump didn’t reduce greenhouse gasses in his buildings.

Threats are standard from maybe-presidential-candidate Blas. Action on climate change is, again, someone else’s problem. “Anyone has a problem with saving the planet, I got a problem with them,” de Blasio blustered during the circus-like press conference. That’s the same Bill de Blasio who hypocritically takes a caravan of cars from Manhattan to Brooklyn to go to the gym. You people need to make changes to “save the planet”; our mayor is above that kind of thing.

The lame excuse de Blasio ­offered in 2017 for why he simply had to work out at a gym 12 miles from where he lives was that he didn’t want to get too sheltered at Gracie Mansion. “I want to be someone who sees the world through the prism of the neighborhood I come from in Brooklyn,” he said. But when a homeless woman, Nathylin Flowers Adesegun, approached him at the gym last October to discuss housing, he told her: “I’m in the middle of doing my workout.” He didn’t feel like looking through the prism just then.

“No one is above the law,” the mayor claimed during his Trump Tower press conference, in ­response to a question about the accident.

Left unsaid: except me, suckers.

Twitter: @Karol