The plaintiffs say the "shelter has a duty to help, not harm, homeless dogs and cats."
The Animal Legal Defense Fund along with three people from Stockton filed the lawsuit against the City of Stockton.
The suit is not asking for money, only that the animal shelter follow the law.
The shelter is required to hold strays for at least 6 days before euthanization.
But Animal Legal Defense Fund Attorney Jenni James says the shelter's records show a different story over a one year period.
"Early euthansias are happening, 1,500 animals were euthanized before the expiration of the Stockton shelter's minimum holding period," says James.
James says 80 percent of the animals are behind locked doors where the public never sees them.
"Only about 20 percent of the animals are truly being given a meaningful chance of adoption," says James.
The City of Stockton is not commenting on the lawsuit.
Stockton has become the first place in the nation to have a rapid transit bus route that is all electric. The new service starts Wednesday.
Startup companies will get a big step up from a team of mentors and investors in Stockton. Entrepreneur Lab 2017 will offer one-on-one sessions to give them a chance at success.
Another attempted shooting of Stockton police last night…the second in less than 3 weeks. As before, it occurred during a routine traffic stop.
There was a deadly collision between a Stockton police patrol vehicle and a sedan early Wednesday morning. There's an ongoing investigation at the accident scene through 6 p.m. Wednesday.
A gunman fired at three Stockton police officers during an attempted traffic stop late Monday night. The attempted homicide had officers diving for cover.