Volkswagen has pled guilty to criminal charges that it cheated diesel emissions tests in the US, according to Reuters. The guilty plea comes as part of a $4.3 billion settlement reached with the Justice Department this past January.

In September last year, the company admitted installing secret software in more than half a million vehicles sold in the US that it used to fool exhaust emissions tests.

The company pled guilty to conspiracy to violate the Clean Air Act, the obstruction of justice, and entry of goods by false statement. The $4.3 billion fine would cover criminal and civil charges from the federal government (including environmental penalties) but is separate from the billions the company has set aside for civil suits with individual car owners.

Including these, the cost of settling various claims is expected to exceed $20 billion in the US, making it one of the most expensive corporate scandals in history. Volkswagen says it’s currently working with US courts to resolve civil claims for vehicle owners, dealerships, and states in which consumer protection laws were violated.

Individual executives may also face additional charges. The Justice Department charged seven current and former VW executives with crimes related to the scandal. Last September, James Liang, a veteran Volkswagen engineer, pled guilty to conspiring to defraud the American public about its vehicle emissions.