Ringling Bros. and its parent company, Feld Entertainment, have defended themselves aggressively since the suit was filed in 2000, contending their treatment of all circus animals is state-of-the-art.

The plaintiffs have asserted that Ringling Bros.' own train records show the elephants are chained in railroad boxcars for an average of more than 26 straight hours, and often 60 to 70 hours at a time, when the circus travels.

The circus also defends the use of bullhooks, saying the sharp tools have been used for centuries in Asia to control elephants humanely. Activists say the implements — which resemble long fire pokers — often inflict wounds that leave scars.

Michelle Pardo, a lawyer for Feld Entertainment, said the defense will prove that the elephants "are healthy, alert, and thriving."

In addition to four animal welfare groups, the plaintiffs include Tom Rider, a former Ringling Bros. employee who alleges that he witnessed abuse of the elephants on numerous occasions.

The main reason I never visit a circus or zoo!

Just because the elephants are still alive does not mean that they are alert and thriving. They are merely existing.