Spike was a 6-year-old, specially-trained Labrador who was left in his handler's SUV on a hot day in 2020.
Spike's death did not become public for more than two years and there were allegations of a cover-up, including a memo where investigators claimed to have spoken with the veterinarian who tried to save Spike's life.
However, veterinarian Dr. Yolanda Cassidy told Eyewitness News last fall that the memo was faked. Cassidy says she never saw Spike, wasn't working that day and was never interviewed by investigators.
Cassidy filed a lawsuit Thursday against the Sheriff's Department and former Sheriff Alex Villanueva, claiming they destroyed her professional reputation.
Villanueva told Eyewitness News there was no cover-up and he stands by that memo.
A department spokesperson issued the following statement:
"The tragic death of our beloved Department K-9 named "Spike" is unfortunate. Due to pending litigation, we are unable to provide further details at this point. However, we can say a supervisory inquiry was conducted in 2020 and precautionary steps have been taken to ensure these incidents do not occur in the future."