An Upper Marlboro defense lawyer pleaded guilty Tuesday in U.S. District court in Alexandria to conspiracy to launder drug money.

Brian W. Young, 39, admitted that William H. Cornman, who later was convicted of drug trafficking, came to him for advice on how to make cash from marijuana sales appear as though it was legitimate income. In 2005, Young accepted $15,000 in drug money from Cornman and invested it in real estate, federal prosecutors said.

After Cornman’s arrest on drug trafficking and firearms charges, prosecutors said, Young received more than $60,000 in cash from Cornman’s drug partners. Young deposited most of that money into his law firm’s account and then issued checks to other attorneys to represent Cornman and a co-conspirator in federal court, according to court papers.

Young asked one of his law partners to hide $15,000 cash of the remaining drug money, and the partner buried the money on property in Aquasco, Md., prosecutors said.

In the courtroom Tuesday, Judge Gerald Bruce Lee asked Young, “How do you plea?

“I plead guilty your honor,” answered Young, wearing a dark gray suit as he stood at the lectern.

Young also made false statements on two IRS forms documenting the receipt of the drug money in an attempt to try to cover up the illegal funds, prosecutors said.

Young faces a maximum sentence of 20 years in prison. His sentencing is scheduled for July 15.