The final defendant in the massive DC Solar fraud has been sentenced, closing a long investigation that uncovered fabricated revenue, deceptive leases, and well over $900 million in investor losses.
The last defendant in this case received a federal prison term this week, bringing a rare close to a sprawling scheme that played out over most of the 2010s. Ronald J. Roach, 59, of Walnut Creek, was sentenced by U.S. District Judge Dale A. Drozd to 66 months in prison. The sentence caps criminal exposure tied to accounting and financial deception inside DC Solar.
Roach served as DC Solar’s accountant and admitted a central role in concealing the company’s true finances from investors and lenders. He and co-defendant Joseph Bayliss were the first DC Solar defendants to plead guilty on Oct. 22, 2019, and Roach’s plea ultimately left no defendant standing for trial. The guilty pleas reflect an investigation that relied on detailed financial tracing and cooperation among multiple agencies.
DC Solar marketed and manufactured mobile solar generators mounted on trailers between 2011 and 2018 and promoted federal tax incentives as a major investment draw. The company represented those generators as earning lease revenue from third-party users, including temporary power for cellphone towers and event lighting. That revenue story proved to be largely fictional once investigators followed the money and documents.
Investigators found that investors rarely took physical possession of the generators they were said to buy. Instead, DC Solar typically leased those assets back from investors and claimed to sublease them to third parties to generate the lease revenue that justified tax credits and investor returns. In practice there was almost no real third-party demand for the equipment, so new investor funds were used to satisfy obligations to earlier investors.
“Today’s sentencing marks the final chapter in an extensive fraud that caused significant loss. This outcome reflects years of careful, methodical investigative work and a prosecution built on meticulous attention to detail,” said U.S. Attorney Eric Grant. “None of the eight defendants went to trial, but each ultimately accepted responsibility and pleaded guilty. Our office remains committed to holding accountable those who exploit others for personal gain. We will continue to pursue justice with diligence and integrity.”
One critical element prosecutors uncovered was how lease revenue on the books was manufactured through intercompany transfers that mimicked outside rentals. During the conspiracy, about 94 percent to 95 percent of the lease revenue on the books was actually intercompany transfers disguised as new investor money. In truth, third-party end-user demand for generators never exceeded five percent of the revenue that was claimed.
“As the company’s accountant, Ronald Roach concealed the truth from investors for years, enabling DC Solar to operate on fabricated financials,” said FBI Sacramento Special Agent in Charge Sid Patel. “This fraud permeated nearly every level of the company’s criminal operations. Today’s sentencing reflects the tireless efforts of FBI Sacramento and our partners at IRS-CI, FDIC-OIG, and the U.S. Attorney’s Office, who spent years methodically dismantling one of the largest fraud schemes in the Eastern District of California.”
The dollar figures attached to the scheme are striking and explain why the case attracted intensive resources. Between March 2011 and Dec. 18, 2018, investors invested approximately $759.4 million, and several financial institutions and other investors transferred $152.7 million to DC Solar as part of related transactions for the purchase and lease of generators. In total, DC Solar closed transactions with investors that contributed more than $912 million to purchase generators; those transactions were purported to involve approximately 17,000 generators, at approximately $2.5 billion in value.
“The sentencing of Ronald Roach underscores the unwavering pursuit of accountability in this far-reaching fraud scheme,” said Linda Nguyen, Special Agent in Charge of IRS Criminal Investigation, Oakland Field Office. “The DC Solar case revealed a deliberate and sweeping effort to abuse federal tax incentives and deceive investors on an extraordinary scale. IRS‑CI, together with our law enforcement partners, remains firmly committed to ensuring every individual responsible is brought to justice.”
The investigation and prosecution set a pattern of interagency cooperation across law enforcement and financial regulators. The FBI, IRS Criminal Investigation, and the Federal Deposit Insurance Corporation Office of Inspector General worked together to unravel the transactions and trace the flow of investor funds. Assistant U.S. Attorneys Audrey B. Hemesath and Nicholas M. Fogg handled the prosecution on behalf of the U.S. Attorney’s Office.
“Mr. Roach ignored his responsibilities as a certified public accountant, conspiring with his co-defendants to defraud individuals, financial institutions, and the U.S. Government,” said Special Agent in Charge Ryan Korner from the Federal Deposit Insurance Corporation Office of Inspector General (FDIC OIG). “This case highlights that no matter how complicated the fraud, FDIC OIG and our law enforcement partners will join forces to unravel the scheme, hold the perpetrators accountable, and bring justice to victims.”
The case produced a series of substantial sentences and restitution orders across multiple defendants, reflecting the scheme’s size and the losses involved. Below is the status of the other seven defendants and the penalties they received in connection with the DC Solar prosecutions.
- Jeff Carpoff, 55, of Martinez, was sentenced on Nov. 9, 2021, to 30 years in prison and ordered to pay $790.6 million in restitution.
- Paulette Carpoff, 52, of Martinez, was sentenced on June 28, 2022, to 11 years and three months in prison.
- 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.
- Alan Hansen, 54, was sentenced on May 31, 2022, to 39 months in prison.
- 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.
- Ari J. Lauer, 61, of Lafayette, was sentenced on March 9, 2026, to 11 years and five months in prison. One week before trial, on Oct. 14, 2025, Lauer pleaded guilty to one count of conspiracy to commit wire and bank fraud, 12 counts of bank fraud, and 10 counts of wire fraud affecting a financial institution.
