New Charges, Sentences For Martinez, Pleasant Hill Execs In $912 M Solar Ponzi Scheme

CONTRA COSTA COUNTY, CA — Prosecutors handed down more indictments in a massive solar fraud scheme involving a Walnut Creek man and several other from across Contra Costa County.

Ronald J. Roach, 57, of Walnut Creek, pleaded guilty to criminal offenses related to the fraud scheme and is scheduled to be sentenced on April 13, 2026. Roach faces a decade in prison.

The newest sentencing involves a Lafayette corporate attorney — who prosecutors say helped keep one of the nation’s largest renewable-energy investment frauds alive for years — will spend more than a decade in federal prison.

Ari J. Lauer, 61, received an 11-year-and-five-month prison sentence on March 9 after admitting he helped orchestrate the sprawling DC Solar fraud scheme, which drew more than $900 million from investors.

A federal judge in the Eastern District of California handed down the sentence, U.S. Attorney Eric Grant said in a news release.

Prosecutors said Lauer’s role as outside counsel helped lend credibility to the company’s operations and reassured investors who poured millions into mobile solar generator projects that largely did not exist.

“Without the participation of Lauer, the DC Solar fraud scheme would never have been operational,” Grant said in a statement. “He used his skill as a corporate lawyer to execute a sophisticated tax scheme that enabled the largest criminal fraud in the history of the Eastern District of California.”

Lauer pleaded guilty Oct. 14, 2025 — one week before his scheduled trial — to conspiracy to commit wire and bank fraud, 12 counts of bank fraud, and 10 counts of wire fraud affecting a financial institution.

Ghost Investors

Investigators said Lauer helped construct a financial structure that hid the scheme’s growing financial holes. The company claimed investors would buy mobile solar generators mounted on trailers, then lease them back to the company, which said it would rent them to third parties for emergency power and event lighting.

But federal investigators said the market for the equipment barely existed. According to court records, investors never actually took possession of most generators. Instead, the company moved investor funds between accounts and labeled the transfers as lease revenue. Conspirators referred to the practice as “re-rent.”

Lauer and other participants even drafted a “re-rent agreement” in 2014 and backdated it to 2011 to justify millions of dollars moving between accounts, prosecutors said.

Between 2011 and 2018, investors poured about $759 million into the scheme, while banks and other institutions transferred another $152.7 million tied to generator purchases and leases.

Altogether, transactions tied to the company exceeded $912 million and involved roughly 17,000 generators valued at about $2.5 billion.Investigators found that about 95% of recorded generator lease revenue came from moving new investor money within company accounts. Less than 5% reflected genuine third-party demand.

FBI Sacramento Special Agent in Charge Sid Patel said Lauer helped cloak the operation with legal credibility. “Ari Lauer intentionally used his position as an attorney to provide the illusion of legitimacy to DC Solar’s fraudulent scheme," Patel said. “Today’s sentence sends a clear message that law enforcement will unravel these lies and dismantle Ponzi schemes.”

Internal Revenue Service Criminal Investigation Oakland Special Agent in Charge Linda Nguyen said the scheme damaged investors and disrupted the clean-energy marketplace.“White-collar crime is not victimless,” Nguyen said. “Our investigators followed the money and uncovered the truth to help secure justice for those harmed.”

Following the conviction, the State Bar of California placed Lauer on involuntary inactive status.

Investigators from the IRS, FBI, and the Federal Deposit Insurance Corporation Office of Inspector General led the investigation.

Several other executives and associates also received prison terms:

• Jeff Carpoff, the scheme’s Martinez founder, was sentenced to 30 years in prison and ordered to pay $790.6 million in restitution. His wife, Paulette Carpoff, received an 11-year-and-three-month sentence.
• Joseph W. Bayliss, 50, of Martinez, was sentenced on Nov. 16, 2021, to three years in prison and ordered to pay $481.3 million in restitution.
• DC Solar CFO Robert A. Karmann, 59, of Clayton, was sentenced on April 12, 2022, to six years in prison and ordered to pay $624 million.
• Ryan Guidry, 49, of Pleasant Hill, was sentenced on Jan. 31, 2023, to six years and six months in prison and ordered to pay $619,415,950 in restitution.
• Alan Hansen, 54, of Vacaville, was sentenced on May 31, 2022, to eight years in prison and ordered to pay $619 million.