A Volkswagen engineer pleaded guilty in Detroit on Friday and agreed to cooperate in the U.S. criminal probe into the German automaker's diesel emissions scandal.
James Liang, 62, was the first person charged in the U.S. investigation, the Justice Department said.
Liang entered a plea agreement that includes his cooperation with the government, a department spokesman said. VW has already agreed to spend up to $16.5 billion to address environmental, state and owner claims in the United States.
Liang pleaded guilty for his role in an almost 10-year conspiracy to defraud U.S. regulators and U.S. customers, according to the Justice Department. In 2006, Liang developed a software "defeat device" to make vehicles appear cleaner than they were. In 2014, he conducted a test to help conceal emissions-cheating, according to the government.
The Justice Department said he pleaded guilty to one count of conspiracy to defraud the U.S., to commit wire fraud and to violate the Clean Air Act. The maximum penalty is five years of imprisonment with a $250,000 fine, according to court documents.
"Volkswagen is continuing to cooperate with the U.S. Department of Justice. We cannot comment on this indictment," the company said in a statement.
— Reuters contributed to this story.