A Catholic priest will be allowed to sue the Diocese of Palm Beach for defamation after a judge this week rejected the diocese’s claim that the constitutional separation of church and state should prevent the lawsuit from being decided in a secular court.

In a four-page order, Palm Beach County Circuit Judge Meenu Sasser said Tuesday that the Rev. John Gallagher’s claim that the diocese defamed him by calling him a liar who needed "professional assistance" can be decided without getting involved in the policies of the Catholic Church.

"This court also notes the public nature of these statements," Sasser wrote in her order allowing Gallagher’s lawsuit to proceed.

The diocese posted three comments on its website vehemently disputing Gallagher’s allegations that it tried to cover up sexual abuse by a visiting priest. And it repeated its dim view of Gallagher’s veracity in a letter that Bishop Gerald Barbarito ordered by read at all Masses in the five-county diocese in January 2016.

While attorneys representing the diocese claimed the lawsuit was barred by the ecclesiastical abstention doctrine, which prevents secular courts from becoming involved in religious affairs, Sasser disagreed.

Gallagher’s defamation lawsuit "can be assessed using neutral principles of law and without resolving a church controversy," she wrote.

Coral Gables attorney Joseph Winsby, who is representing the diocese, wasn’t immediately available for comment.

Attorney Ted Babbitt, who is representing Gallagher, said he expects Winsby will appeal Sasser’s ruling. But Babbitt said he hopes to begin preparing for trial. His first task will taking a deposition of Barbarito. He said he expects the church to challenge those plans as well.

Gallagher, a former pastor at Holy Name of Jesus Catholic Church, sued the church in January. He claimed Barbarito punished him for ignoring instructions not to tell authorities that the Rev. Jose Varkey Palimattom, a visiting priest, had shown pornographic pictures to a 14-year-old youth at the suburban West Palm Beach church in January 2015.

After working with the Palm Beach County Sheriff’s Office to help prosecute Palimattom, Gallagher claims he was locked out of the rectory and the church.

In court papers, Winsby disputed Gallagher’s assertions. "This incident was reported by the diocese to law enforcement immediately and no cover-up was accomplished," he wrote.

However, Winsby said, how the diocese handled Palimattom and Gallagher are rooted in church policies and procedures.

"These questions inextricably intertwine church discipline, ecclesiastical government, and the conformity of the members of the church to the standard of morals required," he wrote. "A jury should not consider those issues pursuant to the First Amendment to the United States Constitution."