The NYPD caught a Trump-loving graffiti artist by building a wall.

There’s been a lot of debate in the past few years over whether building a wall on the U.S.-Mexico border will help curb the flow of undocumented people and drugs into the country.

(For more on why it’s a bad idea, read here.)

But no one is debating the effectiveness of a wall that was built in New York City to arrest a serial graffitist whose pro-Trump vandalism irked fellow riders at the Borough Hall/Court Street station in Brooklyn.

Complaints of pro-Trump graffiti in the subway station began in January.

So some officers hatched a plan to erect a plywood enclosure in the subway station they could hide behind to catch the MAGA vandal in the act.

Lo and behold, the vandal struck again, tagging #LoveTrump in the station and the police popped through the door in the wall to arrest 43-year-old Jamie Montemarano. Montemarano was charged with graffiti and criminal mischief.

“Sure enough, our man came back and put up again in #lovetrump on the beam, so they caught him live writing on the beam,” said NYPD Chief of Transit Edward Delatorre.

It had to be a bitter-sweet moment for Montemarano. He can now happily claim that walls can be effective at deterring crime; unfortunately, this time he was the criminal.