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.
The first debate for the U.S. Senate seat in California takes place Monday at the University of the Pacific in Stockton, and it is causing a lot of excitement on campus.
Low attendance and shrinking revenue have spelled the end for horse racing in Stockton which has been a part of the San Joaquin County Fair in Stockton for over 150 years.
An attempted carjacking in Stockton this morning turned deadly when a police officer shot and killed one suspect while two others escaped.
New York is "The City That Never Sleeps", and for Las Vegas the slogan is "What Happens Here, Stays Here." Now Stockton has a new logo and a new slogan.
Stockton residents can voluntarily have their home water tested by the city for lead and copper levels.