One of the cats showed signs of having been sexually abused, experts said.
The courtroom was packed with the pet owners and their families, neighbors and other animal lovers, many of whom were wearing purple ribbons with white cat paws.
Neighbours in Cambria, San Jose, clubbed together to track down the culprit filmed by Miriam Petrova's home security camera.
Farmer was found sleeping in a auto with a dead cat curled up inside the vehicle in October 2015. Stine was surprised when McKimmie said her cat went missing the same morning as his 16-year-old orange tabby cat Chablis, who still has not been seen to this day.
He had pleaded guilty to 21 counts of animal cruelty prior to sentencing. Prosecutors say he tortured and killed as many as 16 cats in the Cambrian Park neighborhood over a two-month period in the fall of 2015. But Chatman said Friday that none of the animals were tested for semen - apparently because there was no immediate indication they had been sexually assaulted - and none was found on Farmer's clothing or vehicle. Schroeder contested the prosecution's argument that the cat was sexually abused. Ellis also argued Friday that Farmer presented a "phenomenal risk" of re-offending.More news: House Democrats press Treasury to divulge any Trump-Russia financial ties
"The judge did everything she could possibly do", said Olena Klingman.
"He likes to hurt living things", Chatman said.
But the judge declined that request. "The entire veterinary community doesn't study it and so it's not a piece of evidence I can put on your side of the scale".
Farmer was also ordered to stay away from that community and will not be able to own an animal. The defendant did not address the court, but instead wrote a statement that his attorney read on his behalf, blaming the use of meth for what he did. Farmer listened with his back turned to the crowd.
"GoGo never hurt anybody", she added, before addressing Farmer directly: "And for you, Robert Farmer-what have you done to GoGo?" "It'll be not closure completely, but partially".