Volkswagen has pleaded guilty to three charges as part of a $4.3bn (£3.5bn) agreement with the US regulators over the diesel emissions scandal.
The German car maker has pleaded guilty to conspiracy to commit fraud, obstruction of justice and entry of goods by false statement.
VW general counsel Manfred Doess told a court in Detroit the company was "guilty on all three counts".
He said the criminal acts occurred in both Germany and the United States.
'Went to the top'
VW admitted that vehicles were fitted with illegal software which allowed them to cheat emissions tests over a six-year period.
John Neal, an assistant US attorney, told the US district court that the scheme "was a well thought-out, planned offensive that went to the top of the organisation".
Under the deal with the Department of Justice, VW agreed to major reforms and scrutiny by an independent monitor for three years after admitting to installing the secret software in 580,000 US vehicles.
The devices enabled VW's diesel vehicles to emit up to 40 times legally allowable pollution.