Kathryn Keneally will step down as head of the U.S. Department of Justice’s Tax Division next month, DOJ officials said Tuesday.

Keneally oversaw the division for two years, including enforcement against the use of foreign bank accounts to evade U.S. taxes. Credit Suisse Group A.G., charged this month in the U.S. District Court for the Eastern District of Virginia with helping clients avoid paying U.S. taxes, became the largest bank to plead guilty in 20 years.