The evidence seemed overwhelming.

A Los Angeles County Sheriff’s deputy was caught on video stealing trim from an impounded vehicle. Another deputy was captured taking cash after a motorist was shaken down to avoid his car being towed. A third was caught on tape rummaging through an SUV at a tow yard and accused of pilfering designer sunglasses from it.

The case was built around an informant who had worked for the FBI — a tow truck driver given the code name “Captain America.”

The secret recordings he made were enough for local prosecutors to bring corruption charges against three deputies and a sheriff’s parking enforcement officer, alleging bribery and theft.

But, last year, when the first case went to court, the star witness dropped a bombshell.

“Captain America,” it turned out, wasn’t the man sheriff’s investigators thought he was.

Albino Mendoza has been held in an ICE detention facility after helping federal agents target L.A. County sheriff's deputies in a corruption investigation. Robert Gauthier / Los Angeles Times

Albino Mendoza’s instincts were to steer clear when an FBI agent approached him in 2012.

The tow truck driver was living in the country illegally and had a criminal history that included convictions for burglary, credit card fraud, and other crimes, court and FBI records show.

He had been previously deported back to Mexico and then returned to California to live under a fake name, Damian Castillo. With his new identity, he had begun driving for tow companies in the constellation of small, industrial cities that ring Los Angeles to the south. He got married and had three children.

But his wife urged him to work with the FBI, which was investigating allegations of corruption in the county’s tow truck industry. Agents, she said, might be able to help him earn legal status in the country in exchange for his cooperation.

He agreed to become an FBI informant, but kept his real identity and past hidden.

A few months later, he came clean with his handler, Special Agent Jason Dalton, telling him his real name, his past crimes and his illegal status in the country.

Dalton alerted higher-ups in the bureau and the U.S. attorney’s office of the deception and asked if Mendoza’s credibility was too badly compromised to continue as an informant. He was told to keep using him.

For more than two years, Mendoza told Dalton stories of massive corruption. Tow companies, he said, were paying off local politicians and sheriff’s officials with five- and six-figure bribes. Dalton found the claims to be “completely unsubstantiated" and not credible, said FBI spokeswoman Laura Eimiller.

Secret recordings made by Albino Mendoza were enough for local prosecutors to bring corruption charges against three deputies and a sheriff’s parking enforcement officer, alleging bribery and theft. Secret recordings made by Albino Mendoza were enough for local prosecutors to bring corruption charges against three deputies and a sheriff’s parking enforcement officer, alleging bribery and theft. Secret recordings made by Albino Mendoza were enough for local prosecutors to bring corruption charges against three deputies and a sheriff’s parking enforcement officer, alleging bribery and theft. (L.A. County Sheriff's Dept.)

Then, in July 2014, the informant piqued the agent’s interest. He said a group of sheriff’s deputies and parking enforcement officers were preying on motorists.

One deputy, he said, had swiped a PlayStation game console from the impounded car of a homicide victim. Another pilfered car stereos. Others shook down motorists for cash to release impounded vehicles — and Mendoza admitted he had participated.

FBI technicians fitted one of Mendoza’s work shirts with a hidden camera. Over the next few months, Dalton instructed him to record multiple encounters with some of the sheriff’s employees, according to FBI memos, court records and videos.

One night, Deputy Manny Zavala called Mendoza to tell him a motorist was willing to pay cash to avoid being towed, according to FBI memos written by Dalton. The informant collected $380 from the driver and later recorded a meeting with Zavala at a Huntington Park gas station parking lot where he paid the deputy half of the money.

And Mendoza reported to Dalton that two parking enforcement officers arranged for him to collect $190 from a motorist who faced being towed, according to another memo. One of the officers, Marie Cruz, later sidled up to Mendoza.

“So can I get my half?” she said, according to the memo. On a different night, Mendoza recorded a rendezvous where he paid Cruz $160 — her share of bribes paid by two motorists earlier in the evening, FBI records show.

Excerpt of a recording from an FBI sting in August 2014 that targeted an L.A. County sheriff's deputy.

In another exchange, the hidden recorder ran as Deputy Tony Guerrero removed the trim from a vehicle before allowing Mendoza to tow it, FBI memos show.

Dalton set up a sting targeting Deputy Heriberto Fernandez, who Mendoza claimed liked to steal expensive sunglasses and other things from impounded cars, according to FBI reports. At the agent’s direction, Mendoza led the deputy to an SUV equipped with hidden cameras. Inside were a pair of Oakley sunglasses and an envelope with $1,310.

The deputy picked up the cash but worried aloud that nearby security cameras might be watching, according to a transcript of the FBI recording filed in court.

“Hey, give me five bills out of that, all right, dog? Keep the rest,” Fernandez told the informant at one point, suggesting they split the cash, according to the transcript. “Five, six, seven — you keep 800 bucks.”

When Dalton searched the car the following morning, the sunglasses were gone. But the cash was still there.

In the end, none of it amounted to the type of large-scale corruption that federal prosecutors typically handle. The FBI opted to shut down its investigation.

But when sheriff’s investigators caught wind of the FBI’s inquiry, Dalton handed over the evidence he and Mendoza had collected.

The recordings became the crux of the case sheriff’s detectives brought to local prosecutors. In 2015, the Los Angeles County district attorney’s office filed criminal charges against the three deputies and parking enforcement officer.

A guard on security rounds at Adelanto Detention Facility. Irfan Khan / Los Angeles Times

Prosecutors called “Damian Castillo” to the stand last year to testify about the wrongdoing he had witnessed.

But the focus of the preliminary hearing soon turned to the informant’s own murky past.

Richard Hirsch, a veteran defense attorney, asked if he had come to the United States illegally and been deported after getting convicted of a drug offense. Begrudgingly, the informant admitted it was true.

Hirsch accused him of helping the FBI in hopes agents would help him become a legal resident in the U.S. Growing flustered, the informant denied the claim.

The attorney had one more card to play.

“What is your true name?” he asked.

“Albino Manuel Mendoza,” the informant replied.

The revelation came as news to Sgt. Amy Hanson, one of the lead sheriff’s investigators on the case. Hanson later testified she had no idea until that moment that her key witness had a significant criminal record and was living in the country illegally under a fake name.

FBI agents gave their informant the code name “Captain America.” The informant – known in bureau parlance as a “confidential human source” or CHS – and a sheriff’s parking enforcement officer allegedly shared bribes paid by motorists hoping to avoid their cars from being towed. Left, FBI agents gave their informant the code name “Captain America.” Right, The informant – known in bureau parlance as a “confidential human source” or CHS – and a sheriff’s parking enforcement officer allegedly shared bribes paid by motorists hoping to avoid their cars from being towed.

Dalton, she said, had introduced the informant as Damian Castillo and she had no reason to doubt the agent. A transcript of the FBI recording from that initial meeting with Dalton confirms that the agent introduced the informant as Castillo.

For his part, Dalton testified he could not recall alerting sheriff’s investigators to the informant’s true name but believed he did so because it “would have been useful” to their case.

Even during his testimony, however, the agent continued to refer to Mendoza as Castillo.

“I’m used to calling him Castillo,” Dalton insisted. “I think I would be more comfortable calling him Castillo.”

By then, Mendoza’s credibility was destroyed.

Prosecutors didn’t even call him as a witness as the first case went to trial last year.

Superior Court Judge Chet L. Taylor acquitted Fernandez, the deputy accused of stealing the sunglasses. Calling the case “a rotten egg,” the judge sharply criticized both Dalton’s investigation and the informant.

The footage captured in the sting didn’t show who took the sunglasses, which were never recovered. The judge recited the informant’s lengthy rap sheet of past convictions and deceptions.

“This is a guy who is not credible, not credible at all,” Taylor concluded.

I’m used to calling him Castillo. I think I would be more comfortable calling him Castillo. FBI agent Jason Dalton

FBI agent Jason Dalton leaves the stage after attending a May 2015 press conference at the downtown Federal Building. Robert Gauthier / Los Angeles Times

The rest of the corruption cases soon crumbled. Prosecutors announced they would drop misdemeanor petty theft charges against Guerrero, who was accused of stealing car parts.

Prosecutors dropped the bribery charges against the remaining deputy, Zavala, and the parking officer, Cruz. Zavala pleaded no contest to petty theft and Cruz to grand theft. Both avoided jail.

Fernandez and Guerrero remain in the Sheriff’s Department, Sheriff Jim McDonnell said in an interview. The accusations against the deputies are being dealt with “administratively,” said McDonnell, who declined to elaborate, citing state privacy laws. Zavala and Cruz no longer work for the Sheriff's Department.

A lawyer for Cruz declined to comment. Lawyers for the three deputies criticized how the FBI handled the informant and the confusion over his identity.

“At its most benign, it was sloppiness by an agent. At its most sinister, it was a distortion of the criminal justice process,” said attorney Vicki Podberesky.

Dalton declined requests for comment. Eimiller, the FBI spokeswoman, said Dalton dealt with the informant and sheriff’s investigators appropriately.

Brandon Fox, who recently left his job as an assistant U.S. attorney in charge of the public corruption unit that oversaw Dalton’s case, said sheriff’s investigators should have done more to learn the truth about the informant.

“The Sheriff’s Department had the obligation to perform its own investigation,” he said in an interview. “It needed to follow its own rules for determining the credibility of its sources.”

McDonnell defended his investigators.

“In general, if you get a case from another law enforcement agency, you give credence to the fact that it is coming from seasoned professionals,” the sheriff said.

Mendoza has been released from the Adelanto Detention Facility. Robert Gauthier / Los Angeles Times

Mendoza wasn’t around to see the cases fall apart.

While he worked as an informant for Dalton, immigration officials had agreed not to go after him. But a few weeks after his real identity was revealed in court, Mendoza was driving alone when immigration agents pulled him over.

He was sent to a detention facility a few hours outside of Los Angeles in the Mojave Desert, where he spent the next six months. While he was locked up, his wife gave birth to their fourth child.

An immigration judge released him in December and will ultimately decide whether he should be deported.

Wearing a location tracker strapped to his ankle, Mendoza spends most of his days at home, broke and bitter. A $5,000 payment the FBI had given him for his services was spent long ago. Mendoza claims Dalton promised to help him obtain legal residence; Dalton denies making such a promise.

Looking back on it now, Mendoza said, “I should have just minded my own business.”

Support our journalism Already a subscriber? Thank you for your support. If you are not, please consider subscribing today. Get full access to our signature journalism for just 99 cents for the first four weeks.

joel.rubin@latimes.com | Twitter: @joelrubin

matt.hamilton@latimes.com | Twitter: @MattHjourno

ALSO

'They are damn lies': LAPD chief lashes out after captain accuses department of phony crime statistics

Three Pomona police officers are charged in the beating of a teen and coverup

Ex-L.A. Sheriff Lee Baca to stay out of prison while he appeals his conviction