BILLINGS, Mont. >> Federal prosecutors are recommending a former Montana House majority leader be sentenced to 28 years in prison for operating a drug trafficking ring that brought large volumes of methamphetamine into the state.

Court documents filed last week by prosecutors describe former lawmaker Michael David Lange as “the central player” in a conspiracy that brought at least 20 and possibly up to 50 pounds of the drug into the Billings area over a seven-month period in 2016.

Lange, 57, pleaded guilty in September to conspiracy to possess and distribute methamphetamine and possession of methamphetamine with the intent to distribute.

Sentencing is set for Jan. 18 before U.S. District Judge Susan Watters. Each count carries a mandatory minimum of 10 years to life in prison and a $10 million fine.

“Lange was responsible for polluting the Billings community and surrounding areas with a significant quantity of highly pure methamphetamine,” Assistant U.S. Attorney John Sullivan wrote in the government’s sentencing request. “The negative impact associated with at least 20 pounds of methamphetamine is difficult to overstate.”

Lange’s sentencing request was filed under seal. His defense attorney, Ashley Harada, asked the court to shield the document from public release because it contained “sensitive material related to (Lange’s) case strategy and ongoing criminal investigations.”

Harada did not immediately respond to requests for comment.

During his three two-year terms in the Legislature, Lange, a Republican from Billings, supported giving $4 million in state money to an anti-methamphetamine public relations campaign, the Montana Meth Project. He was ousted from his leadership position in 2007 after being captured on video in a profane tirade against then-Gov. Brian Schweitzer, a Democrat.

Lange did not seek re-election in 2008 following the end of his third term. He campaigned unsuccessfully that year for the Republican nomination to challenge former U.S. Sen. Max Baucus.

Prosecutors said Lange lived a crime-free life until his early 50s, when he was charged with driving under the influence in 2014. That August, he committed a second DUI in conjunction with a felony charge of possessing over an ounce of methamphetamine in California and was sentenced to 16 months in prison, according to court records.

Shortly after his release, prosecutors said, Lange began dealing in large quantities of the drug, which was brought in from to California for distribution around Billings. A search of his house in October 2016 turned up more than 2.5 pounds of meth along with more than 13 ounces of cocaine and $27,400, authorities said.

A co-defendant, Jose Soltero, has pleaded guilty to a single count of conspiracy to possess and distribute methamphetamine.

Prosecutors recommended Soltero receive almost 20 years in prison. They alleged he acted as a middleman between Lange and a drug supplier in California identified in court documents only by a nickname, “Manny.”

Soltero’s attorney, Lance Lundvall, downplayed his client’s role in the case and requested a sentence of five years in prison.

Lundvall alleged that Soltero and members of his family had been threatened with violence if they did not participate in the conspiracy.