DENVER — Dudley Brown, the leader of Rocky Mountain Gun Owners, is breathing a sigh of relief after a judge threw out a portion of a lawsuit filed over attack mailers he helped coordinate that used a photo of a gay New Jersey couple kissing without their permission.

U.S. District Court Judge Wiley Daniel ruled that the plaintiffs, the couple and their photographer, have “a plausible copyright infringement claim” but that RMGO was within its First Amendment rights to use the photo because it didn’t identify the couple by name or likeness and because the use related to a matter of public concern.

“We are happy the court has ruled that the defendants’ unauthorized use of the engagement photo may violate the copyright laws and that the copyright claim may proceed to trial,” said Anjali Nair, the attorney for the Southern Poverty Law Center, which brought the suit.

“We are disappointed with the court’s legal ruling on the misappropriation claim and remain convinced that the misuse of our clients’ private engagement photo was wrong.”

RMGO, which bills itself as a “no compromises” Second Amendment organization, coordinated the mailers with Public Advocate, which the SPLC designates as a hate group, to attack former Sen. Jean White, R-Hayden, in a GOP primary over her support for legislation allowing civil unions.

On the mailer, Brian Edwards and Thomas Privitere were shown kissing — their engagement photo, having been used by Public Advocate, which PhotoShopped out the Brooklyn Bridge and Manhattan skyline and replaced it with a more Colorado-appropriate stock image of snow-covered pine trees.

The lawsuit, filed in the U.S. District Court for the District of Colorado, charges that the likeness and personalities of the couple were misappropriated. It also charges that the mailers infringed on the photographer’s exclusive right to the photo, which is registered with the U.S. Copyright Office.