Ending a trial that explored the question of whether graffiti, despite its transient nature, should be recognized as art, a jury found on Tuesday that a New York City real estate developer broke the law when he tore down the so-called 5Pointz complex in Queens three years ago. Along with the buildings nearly 50 swirling, colorful murals that had been spray-painted on its walls were lost.

The finding by the jury, in Federal District Court in Brooklyn, will serve as a recommendation to the judge who presided over the case and who will render a final verdict.

For the better part of 20 years, 5Pointz, a complex of buildings in Long Island City, was a New York rarity: an aesthetic collaboration between the developer, Jerry Wolkoff, and a scrappy crew of graffiti artists that not only became an offbeat tourist destination, but also helped transform the neighborhood into a thriving residential enclave. Though it eventually became what a lawyer for the artists called the “world’s largest open-air aerosol museum,” its existence was always predicated on Mr. Wolkoff tearing it down and turning the buildings into luxury apartments, which he ultimately did in 2014.

When the artists learned about the demolition, they filed suit against Mr. Wolkoff in Federal District Court in Brooklyn, accusing him of violating the Visual Artists Rights Act, which has been used to protect public art of “recognized stature” created on someone else’s property. During the trial, the artists’ lawyer, Eric Baum, claimed that Mr. Wolkoff had failed to give his clients the proper 90-day notice before he destroyed their work by sending in a team of workers one night to cover it in a coat of white paint.