Special prosecutor Matt Powell said he plans to present the criminal case to grand jurors sometime next month. Marsh faces six counts of sexual assault and five counts of sexual performance by a child. The charges involve two boys, ages 15 and 16.
Last weekend, attorneys announced they had settled civil lawsuits accusing Marsh of molesting 10 teens. Terms of the settlement were not released.
"It's not going to affect us at all," Powell said in an interview Thursday. "They don't have any bearing on what I'm going to do."
Marsh's criminal attorneys, who have denied the allegations, declined to comment.
Marsh, 74, is free on $300,000 bond. If convicted, he faces up to 20 years in prison per count and fines of up to $10,000. The charges involve alleged acts from 2010.
Marsh suffered a massive stroke in 2011, and his wife is now his legal guardian.
Powell, who said additional charges against Marsh could be added, said he isn't concerned the settlement could keep the accusers from testifying truthfully.
"That's the reason we have statements from them," he said, adding that statements have been taken from "almost" every alleged victim, not just
The civil suits alleged Marsh gave the teenage boys cash, alcohol, drugs and cars to perform sex acts with him during secret encounters.
Hours after an arrest warrant was issued in November, Marsh turned himself in to authorities. A statement from his lawyers then noted the accusers had filed civil suits "seeking millions of dollars" and that they had waited to come forward until after Marsh had suffered a stroke.
Amarillo police say that they found evidence in Marsh's downtown offices that corroborated "the accounts of sexual exploitation of minors." Police seized computers, couch cushion covers, a photo of a nude male, and signed confidentiality agreements, among other things, according to a search warrant inventory report.
It's not the first time Marsh has been accused of sexual misconduct. In 2001, four lawsuits against Marsh that alleged imprisonment, sexual misconduct and harassment of teens were settled. No other details were made public.
In 1998, Marsh pleaded no contest to misdemeanor charges of unlawful restraint and criminal trespassing as part of an agreement that dismissed five felony charges that included kidnapping, aggravated assault with a deadly weapon and indecency with a child. He served 10 days in jail and paid $4,000 in fines.
In 1996, Marsh settled a lawsuit with a youth who claimed Marsh sexually abused him.
Marsh, who uses the Arabic numeral '3' in his legal name, is probably best known for having 10 brightly painted Cadillacs planted nose down along Interstate 40 in the Texas Panhandle in the 1970s. The cars, ranging from a 1948 club coupe to a 1963 sedan and gathered from junkyards, private collectors and used car lots, have since become a pop art landmark.