Federal prosecutors float 12-year prison sentence for Ken Mattson as part of change in plea

Federal prosecutors and Ken Mattson are weighing an agreement in which the indicted Sonoma real estate investment mogul would plead guilty to one count of wire fraud, along with a sentence of no more than 12 years in prison and a pledge to pay "full restitution" to victims of the "classic Ponzi scheme" authorities say he orchestrated.

Those details were provided in an April 29 letter to investors from a victim-witness specialist in the U.S. Attorney's Office in San Jose, and later shared with The Press Democrat.

But as Mattson's May 11 change of plea hearing approaches, veteran lawyers counsel that the deal is anything but a foregone conclusion. A lot can happen before, and even after, attorneys representing the two sides formally submit their plea agreement to U.S. District Court Judge Jon S. Tigar.

"The devil's always in the details," said Traci Carrillo, a Santa Rosa defense attorney who is not involved in the case. "Until you have a signed agreement, it's never a sure thing."

Mattson originally pleaded not guilty, in May 2025, to seven counts of wire fraud and one count each of money laundering and obstruction of justice. The charges stemmed from what U.S. attorneys alleged were calculated actions on the part of Mattson over at least 15 years to bilk $100 million or more from hundreds of investors, including many mom-and-pop clients. He had attracted their business, often through church circles, with a promise of solid returns based on stakes in a wide range of residential and commercial California real estate plays.

But Mattson wound up using new investments to pay off existing clients, prosecutors said, while diverting money from refinance loans into his own secretive accounts - a house of cards that eventually collapsed.

Observers, including some of those investors, were stunned at an April 10 status conference in Tigar's Oakland courtroom, when prosecutors informed the judge that Mattson had offered to change his plea to guilty.

Changes of plea are not uncommon in high-stakes cases. Throughout any complicated proceeding, starting from the very beginning, "Everyone is constantly evaluating their strengths and weaknesses, and seeing if there's a middle ground they can come to," Carrillo said.

Dropping felony counts is one move available to prosecutors.

"There are a lot of different bargaining chips," said George Fisher, the Judge John Crown Professor of Law at Stanford Law School and a former assistant attorney general in Massachusetts. "If you drop counts, that's a big chip for the prosecution."

For the defense, dragging out a failing case comes with risk.

"Even though judges aren't supposed to punish a client for extending the length of a case, it can be kind of a ‘trial tax,'" Carrillo observed. "There are often benefits for early acceptance of guilt."

Changing his plea to guilty allows Mattson to avoid that risk. And to save money on legal fees.

Last July, Mattson asked the court for permission to remove three properties from his bond agreement and to sell them, arguing that he and his wife, Stacy, were running out of money needed to pay for Ken's defense. That request was denied.

Mattson and his counsel met with U.S. attorneys in early April to review their body of evidence in the case. The defense signaled a change of plea after that.

The pivot to a plea hearing scheduled for May 11 is encouraging for those seeking quicker resolution to the case, according to Naomi Chung, a San Francisco criminal defense attorney. If negotiations weren't going well, she said, they probably would have set a routine status conference instead.

But the deal could still fall apart.

"Any one of the three important players could scuttle it," Fisher said. "By that, I mean the defense, the prosecution and the judge."

Until the plea is formally entered and accepted by the judge, a defendant can back out at any point, Fisher said.

Another thing that could hold up sentencing, according to Chung, is the defendant seeking a "global resolution" to multiple cases. In Mattson's example, he was sued by the U.S. Securities and Exchange Commission around the same time he was charged by the Department of Justice; the civil case was put on hold by the criminal prosecution.

Likewise, the government could reject the terms sought offered by a defendant such as Mattson.

And finally, even if both sides agree to a deal, the judge could reject the plea. That outcome appears unlikely in the Mattson case, though.

Judge has leeway in sentencing

There are three types of plea arrangements in federal courts, as established by Rule 11(c)(1) of the Federal Rules of Criminal Procedure. The most common are (c)(1)(b) deals, in which the opposing parties agree on sentencing guidelines and basic facts, but allow the judge latitude in imposing a sentence.

The victim-witness specialist's letter seemed to describe a (b) agreement. And rarely do you see a judge reject one of those, according to Chung.

Under the plea proposal outlined by the specialist, Mattson would "admit to the full factual basis of the fraud charges in the pending Indictment," and would be obligated to identify all his assets and financial interests, including real estate, whether they're held in his name or another entity's.

As the victim-witness specialist noted in her letter, Tigar isn't bound to accept a 12-year sentence for Mattson, if that's what the two sides end up submitting. He is free to impose any term up to the 20-year maximum while taking into account "the nature and circumstances of the offense and the history and characteristics of the defendant."

It's a concept known as "relevant conduct." And that's where the investors could play a role in sentencing.

They have been invited to submit written impact statements, and some will be afforded the opportunity to read them aloud in court. That will happen at the sentencing hearing to follow, and possibly at the May 11 change of plea hearing, too.

Can those statements really have an impact, though?

You bet, the experts agree.

"The victim having that voice, especially when there's a change of plea in sentencing, is very powerful," Carrillo said. "Often it's the first time the court is hearing them. I've seen judges walk off the bench in tears, and have to compose themselves and come back."

Mattson investors were allowed to submit and read impact statements at an emotional detention hearing in May 2025, but that was before a magistrate judge, Alex Tse.

If the two sides in the Mattson case are still negotiating and bickering over details, Chung said, it's probably about the "loss calculation" that will determine restitution.

"I'm sure both sides have forensic teams looking at that," the attorney said.

Court documents have cited $100 million or more in potential fraud traced to Mattson. But landing on a number has been incredibly hard, because of the businessman's tangled financial transactions and shoddy bookkeeping.

If he accepts the plea agreement, Judge Tigar will be charged with determining how much money is owed to Mattson's investors, and the remaining assets he has to pay those people with.

"If the defense is now penniless, then restitution is just form," Fisher said. "But if he has residual reserves, the victims will want them. The court will want to make victims whole, and the prosecution should as well."

Beachfront property and neon signs

Mattson's assets, which have been a constant source of speculation among his investors, were highlighted in a burst of court filings in late March. Attorneys representing his defunct partnership, LeFever Mattson, which is in bankruptcy and out of Ken Mattson's control, requested permission to sell off his collection of vintage neon signs, questioning whether he personally owned them.

Mattson filed an objection the next day, attaching receipts that showed he paid a Las Vegas antique dealer a total of $85,000 for 20 neon signs and some shipping and repair fees, in 2007. The bankruptcy judge granted the government's request.

Playing into the restitution calculation is the sale of property through the consolidated bankruptcy cases of two entities - LeFever Mattson, which Ken Mattson founded with Tim LeFever, and KS Mattson Partners, a 50-50 partnership between Ken and Stacy Mattson. Together, the two companies purchased more than 200 properties across California, including around 120 in Sonoma.

The real estate sales are long underway, with money going into a fund to compensate Mattson's creditors, including defrauded investors.

In a separate April 20 letter to investors, federal prosecutors announced that the government intends to release its claims to four properties owned by Ken Mattson or KS Mattson Partners - or, in one case, a more complicated ownership structure - so the parcels can be sold out of bankruptcy.

The properties include the Mattsons' mansion in Piedmont, the wealthy enclave surrounded by Oakland, a vacant parcel on the same site and two San Diego County residential properties near the beach in Del Mar. The government had placed notices of lis pendens - basically, a warning to potential buyers that the property title is clouded - on each of them, arguing they were gained in part through the proceeds of "Mr. Mattson's fraud scheme."

"We believe that allowing the bankruptcy estates to distribute this money will allow victims to recover it more quickly than if we waited for the criminal case to conclude," the prosecutors told investors.

One of the Del Mar properties recently sold for $12 million, and the Piedmont backlot went for $1.335 million.

One factor likely to please Mattson's aggrieved investors: If he is convicted and the court can't locate enough money to make the victims whole, anything still owed is a debt that follows him into the future.

The government can seize money - however modest - Mattson is able to earn while imprisoned, garnish his wages after release, attach a lien to any property he buys, and examine his "retirement accounts and whatnot," as Chung put it. That work is done by the DOJ's Financial Litigation/Asset Recovery Unit.

Tigar requested the plea agreement by May 8, but he will not be delivering a verdict at the May 11 plea-change hearing. That session is meant to ensure Mattson is pleading guilty voluntarily, and that the facts are sufficient to establish his guilt.

If those conditions are met, Tigar will schedule a separate sentencing hearing for three or four months later.

You can reach Phil Barber at 707-521-5263 or phil.barber@pressdemocrat.com. On X (Twitter) @Skinny_Post.

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