By Robert Salonga
Bay Area News Group
SAN JOSE, Calif. — A former Santa Clara County correctional deputy convicted of helping jail inmates ambush another inmate four years ago was sentenced Tuesday to 45 days in jail, following a trial that accused him of clearing the way for the attack then trying to cover it up.
Francisco Izayas Castillo, 42, was found guilty March 13 of misdemeanor battery in connection with a Sept. 21, 2022 encounter where two incarcerated men entered the housing unit of another man and beat him. Castillo was charged on the premise that while he did not directly injure the victim, the attack occurred with his blessing and aid.
“Correctional officers are sworn to protect the public and the inmates,” District Attorney Jeff Rosen said in a statement Tuesday. “This officer betrayed the public, betrayed the inmates, and betrayed the badge. My office will hold corrupt correctional officers to account for their behavior.”
The county Sheriff’s Office, which runs the county jails, told this news organization that Castillo was fired in November 2024 .
“The Sheriff’s Office expects all employees to be accountable for their actions, and when conduct undermines the trust placed in us by the community, we respond accordingly,” the agency said in a statement.
A sentencing memo filed by Deputy District Attorney Jason Malinsky asked Judge Brooke Blecher for a 60-day jail sentence to account for Castillo abusing his authority and violating his duty to keep the men under his supervision safe. Blecher ordered Castillo to report to jail June 9.
Shortly before the sentencing, Castillo’s attorney Nelson McElmurry filed a motion for a new trial, which was denied by the judge. He then asked Blecher to stay her ruling pending the outcome of an appeal he intends to file, and was also denied.
“(Castillo) absolutely maintains his innocence and and plans to continue fighting,” McElmurry said Tuesday.
The conviction joins a running list of jail controversies for the Sheriff’s Office, mostly occurring during the previous administration under Laurie Smith and costing the county more than $20 million in legal settlements. The county jails are currently under a federal consent decree to improve jail conditions, based on a lawsuit that paralleled the infamous 2015 beating death of mentally inmate Michael Tyree at the Main Jail, which spurred a host of reform recommendations that eventually led to the county establishing civilian oversight.
According to authorities, on the day of the attack, Adrian and Roney Martinez, who were inmate trustees in Module 4C at Elmwood, approached Castillo’s desk and discussed attacking the victim inmate. Castillo allegedly told the pair to “handle it,” and allowed Adrian Martinez to take rubber gloves from the deputy’s desk.
The investigation determined that Castillo used his control panel to unlock the third inmate’s cell; while the pair were in his line of sight, they pulled open the door, entered the cell and proceeded to punch and kick the victim. When the beaten man activated the emergency call button in the cell, Castillo responded by silencing the alert, later ignoring the man’s claim that he had been attacked, and his subsequent request to be moved to another dorm.
None of Castillo’s response to the victim regarding the attack was recorded on his body camera, which violated policy, authorities said.
Castillo also allegedly ignored the two Martinez men, who are not related, when they later went to the victim’s unit and warned him against reporting the attack, implying that he would face retribution even if he moved to another housing area.
Even after other inmates noticed the victim’s head injuries as he stood in a line, Castillo did not acknowledge the attack. It was only after shift change — about 13 hours after the beating — that another correctional deputy asked the victim about his black eye, prompting the victim to claim that he fell.
Suspecting that something was amiss, the second deputy brought the victim into a room under the guise of a virtual attorney meeting, where he could ask about the injuries without drawing suspicion from other inmates. Eventually, the victim corroborated the attack to the deputy.
What appears to have sparked suspicion of Castillo is his decision to remove the Martinez men’s trustee status — which bestows them modest privileges and elevated status among their peers — after learning that the attack was now known to other staff. That prompted the men to turn on Castillo, and they detailed his complicity, according to the investigation.
That was bolstered by a text message that he later sent to friends and was admitted as evidence, stating, “I’m on admin leave cuz I let 2 guys fight.”
Castillo, who testified in his defense, denied the allegations and said he had no knowledge about what the Martinez men were going to do. McElmurry contends that his client, in telling the Martinez men to “handle it,” was alluding to their leadership roles as trustees to resolve their conflict with the victim.
McElmurry argued that no convincing motive was established for why Castillo would permit the beating, and sought to reframe the text message as his client soberly describing that he was being blamed for the attack. He added that the attackers’ accounts need to instead be viewed skeptically through the lens of men angered after losing their privileges for fighting.
“There’s smoke here, but no fire,” McElmurry said.
Three other men charged alongside Castillo — all inmates at the time — had pleaded no contest to the same battery charge before Castillo’s trial. That included the two Martinez men and Joseph Hernandez , who did not participate in the beating but was characterized as a lookout who warded off attention from other inmates while the attack was underway.
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