In this Monday, March 7, 2011 photo, killer whale Tilikum, right, watches as SeaWorld Orlando trainers take a break during a training session at the theme park's Shamu Stadium in Orlando, Fla. In an unprecedented lawsuit, People for the Ethical Treatment of Animals is accusing the SeaWorld marine parks of keeping five of its star-performer killer whales in conditions that violate the Constitution's ban on slavery. The suit, which PETA says it will file Wednesday, Oct. 26, 2011 in U.S. District Court in San Diego, hinges on the fact that the 13th Amendment, while prohibiting slavery and involuntary servitude, does not specify that only humans can be victims. (AP Photo/Phelan M. Ebenhack)
February 6, 2012 12:24:59 PM PST
by JULIE WATSON Associated Press
SAN DIEGO - February 6, 2012 --
A federal judge in San Diego has heard arguments in a case that could determine whether animals enjoy the same constitutional protection against slavery as human beings.