Hot off the heels of a major victory for pop star Britney Spears, Hollywood litigator Mathew Rosengart is stepping into yet another guardianship case for a high-profile individual: iconic artist Peter Max, whose family is fighting to get him out of the court-ordered arrangement.

Max, the German American artist known for his use of bright colors, psychedelic style and pop art that often includes American symbolism, is under a guardianship that his family says has isolated him, medicated him and stripped him of civil liberties.

Max, who is 84, helped refurbish the Statue of Liberty and created works of art for many U.S. presidents, including Kennedy, Ford, Carter, Reagan and Bush.

“I am honored to join the team’s laudable efforts to seek justice for Peter Max,” said Rosengart in a statement obtained by Variety. “This typifies the type of guardianship that merits judicial attention and potential state and federal legislation. Guardianships and governmental intervention should be an absolute last resort and this case warrants a fresh look and implementation of less restrictive measures and the restoration of basic human rights. We will fight vigorously to obtain newfound freedoms for this American icon.”

Max’s daughter, Libra Max, has petitioned to end the guardianship of her world-renowned father, which she calls “predatory.”

Max’s daughter claims that her father has been isolated with no access to his phone, his emotional support pets taken away and his friends and family unable to visit him, unless they have permission from his guardian and agree to sign nondisclosure agreements. She says that her father’s guardians and court-appointed attorneys continue to bill his estate hundreds of thousands of dollars every year without his consent or knowledge.

“My father has a network of family and friends who want to be with him in the twilight of his life. The abuse he has faced at the hands of the predatory guardianship system is incomprehensible,” said Libra Max in a prepared statement. “I am thrilled Matt agreed to join our team in fighting for my father. This guardianship must end.”

Max’s case marks the next major guardianship fight for Rosengart, who has been hailed as a hero by the #FreeBritney movement after he and his firm successfully worked to get Spears’ father suspended from her conservatorship, and then terminated the arrangement earlier this month after more than 13 years.

Rosengart — a former federal prosecutor who has worked with many A-listers including Sean Penn, Steven Spielberg, Julia Louis-Dreyfus and is currently representing Facebook — continues his work on Spears’ case, as the Princess of Pop faces an uphill legal battle, fighting for justice against her father and former manager of her estate, Tri Star Sports & Entertainment Group.

After Spears’ victorious hearing when her conservatorship was terminated, Rosengart was asked during a courthouse press conference if he would represent actor Amanda Bynes, who is under a conservatorship. “I haven’t been asked, and that’s not something I would get into right now,” Rosengart responded to the question about the former “All That” child star.

Similar to Spears, whose fans started the #FreeBritney movement to fight for her freedom when they first said she was being held against her will, a #FreePeterMax campaign has also started for the artist, garnering thousands of signatures.

A hearing in Max’s case is scheduled for Nov. 30 in New York State Supreme Court.