People for the Ethical Treatment of Animals argued to U.S. District Judge Jeffrey Miller an animal, in this particular case wild-caught orcas, are entitled to protection under the Constitution, The San Diego Union-Tribune reported.
Jeff Kerr, an attorney for PETA, said the case is on the "next frontier of civil rights" law.
Theodore Shaw, SeaWorld's attorney, argued the case should be tossed out of court for lack of merit.
"There are boundaries to legitimate constitutional debate," Shaw said. "And PETA's complaint has crossed those boundaries."
Miller heard about an hour of arguments and said he'd take the case under advisement and rule on it later, the newspaper said.