The man was walking his 7-pound Yorkshire Terrier named "Shadow" near Winchester Boulevard before the alleged incident on Feb. 11.
Three teen boys arrested last month for allegedly assaulting a man in San Jose and killing his dog will also be charged with animal cruelty, but will not be charged as adults, according to a prosecutor.
Authorities said the two 15-year-olds and 16-year-old were responsible for attacking a 32-year-old man the afternoon of Feb. 11 while he walked his 7-pound Yorkshire Terrier on Colonial Way near South Winchester Boulevard.
The trio allegedly attacked the man because he was wearing red, which is a rival gang color, according to Deputy District Attorney Chris Arriola.
Witnesses said the boys had just come from a fundraising carwash for the family of local man Ramon Ruano, 20, who had been killed in a gang-related shooting a week earlier.
The victim's terrier, "Shadow", died after being stomped on or kicked in the assault, according to San Jose Animal Care and Services.
Now, the Santa Clara County District Attorney's Office is adding an animal cruelty charge to the original charges of felony assault with a gang enhancement, Arriola said.
"I think it's very clear according to the evidence that they were trying to attack the victim because he was wearing red, and the dog was injured because of the assault," the prosecutor said.
"They are criminally responsible for what happened by what they set in motion."
The office has also decided not to charge the three suspects as adults after considering their age, criminal history and other circumstances, Arriola said.
"What's scary about this is that the three men attacked a man who was walking his dog for wearing red, and he has no gang affiliation," the attorney said.
Arriola credited San Jose police for "quickly tracking these three young men down and taking them off the street and making that neighborhood a little safer."