PORTLAND, Maine — An activist being sued for defamation over his claims that a Haiti orphanage founder is a serial pedophile contends the lawsuit violates a Maine law that protects residents from meritless suits that aim to chill First Amendment rights.

Lawyers for Paul Kendrick asked a state judge to dismiss the lawsuit, saying his activism aimed at generating attention on behalf of abused orphans is protected speech.

Kendrick said Friday that state law prevents institutions from using costly lawsuits to stymie free speech intended to petition the government.

“Every time I’m shouting from the rooftops, my intention is to garner the support of the public and law enforcement to do something about this,” he said.

The defamation litigation has been dragging on for years. Orphanage founder Michael Geilenfeld and a U.S. charity, Hearts With Haiti, first sued Kendrick in 2013.

A federal jury awarded $14.5 million to Geilenfeld and Hearts with Haiti despite testimony from seven men who said they were sexually abused as boys. But the verdict was overturned after a U.S. appeals court ruled that a federal courtroom was the wrong jurisdiction.

Now attorneys for Geilenfeld and Hearts with Haiti are suing in a state courtroom, bringing essentially the same allegations against Kendrick as before.

The state law Kendrick refers to is known as the anti-SLAPP statute. The acronym stands for Strategic Lawsuit Against Public Participation. The law is being used increasingly in defamation lawsuits, said Dmitry Bam, a University of Maine Law School professor.

“The court has to make an assessment, a quick look on the merits, and get a sense whether the claim is frivolous or being used aggressively to deter what may be lawful conduct,” he said.

The law firm representing Geilenfeld and Hearts With Haiti had no immediate comment.

The lawsuits claimed Kendrick made unsubstantiated accusations that defamed Geilenfeld and cost the charity several million dollars in donations. Geilenfeld also blames Kendrick’s campaign for his 237-day imprisonment in Haiti. The charges were later dismissed.

Kendrick, who helped form the lay group Voice of the Faithful at the height of the clergy sex-abuse scandal, contends more Haiti men have surfaced after the federal civil trial and are willing to testify that they were sexually abused. There are more than a dozen victims, most of whom will travel to Maine to tell their stories, he said.