Mr. Avenatti put most of the client money toward his own expenses, the authorities said, including a $5 million private jet that he co-owned, which prosecutors said they had seized on Wednesday. In the purchase of that aircraft, according to the charging documents unsealed Thursday, Mr. Avenatti used $2.5 million of a client’s $3 million settlement, paid in 2017, while he told the client that the settlement would be paid in installments over eight years.

In other instances, the indictment said, he put client money toward paying personal legal expenses, paying creditors after his firm had filed for bankruptcy, and paying costs associated with a coffee company he owned.

He also dodged taxes, some that he owed himself and others that were owed by his firm, prosecutors said. They alleged that Mr. Avenatti had lied to an I.R.S. revenue officer and had taken steps to prevent the government from collecting on tax liens and levies since 2013.

Though from 2015 to 2017 he withheld taxes from the paychecks of employees at the coffee company he owned — Global Baristas, which ran Tully’s coffee stores — Mr. Avenatti failed to pay more than $3 million in payroll taxes to the government, prosecutors said. They accused him of trying to obstruct the government’s efforts to collect nearly $5 million in unpaid payroll taxes and penalties by routing coffee-company money to different bank accounts, including one associated with a car-racing company he owned.

“As the tax filing season comes to an end, the indictment filed today sends a clear message,” Ryan Korner, the acting special agent in charge of the I.R.S.’s Criminal Investigation division in Los Angeles, said Thursday. “We will investigate all individuals, including high-profile attorneys who violate the tax laws.”

At the time of Thursday’s announcement, Mr. Avenatti was out on $300,000 bail after having been arrested late last month in New York, where he was accused of demanding millions from Nike’s lawyers while threatening to reveal what he has described as improper payments to college basketball recruits by the sportswear giant. He is due to answer to the new charges against him on April 29 in federal court in Santa Ana.

“I intend to fully fight all charges and plead not guilty,” Mr. Avenatti said on Twitter after the new charges in California were announced. “I look forward to the entire truth being known as opposed to a one-sided version meant to sideline me.”