While a lawyer, he was known for filing a high number of lawsuits against media organizations on behalf of photographers who assert that their images have been used without permission,[4] and for receiving multiple disciplinary sanctions culminating in his suspension from practicing law in New York and ultimately in his disbarment.

His experience with Cotler, about which he wrote a book,[6] and as a member of the New York Press Photographers Association motivated Liebowitz to pursue a career in copyright law.

[7] Contrary to other copyright lawyers, his practice is to immediately file suit rather than pursue a settlement, and to claim statutory damages far in excess of the images' ordinary licensing prices.

[7] Media organizations and their lawyers have asserted that Liebowitz is abusing the legal system by overloading the courts with dubious cases in which he attempts to leverage mistakes by overworked editorial staff into financial windfalls.

[7] For his part, Liebowitz has argued that copyright law is the only tool that photographers have to protect their rights and livelihood in a digital media environment in which images are often reused without regard to proper licensing.