As expected, Harriette Walters entered a plea of guilty today, admitting to her role as the head of an elaborate scheme that pilfered almost $50 million from District of Columbia taxpayers.

The former mid-level manager at the D.C. Office of Tax and Revenue is expected to serve up to 18 years in prison, pending approval by Judge Emmet Sullivan.

In a lengthy report to the court based on extensive interviews with Walters, prosecutors finally confirmed something that’s been wondered about since the scandal broke: in the mid-1980s, someone in the Tax office taught Walters how to accomplish her method of creating fraudulent refund checks. Walters has pleaded guilty for the time she took over the scam, from 1989 through 2007. The person who taught Walters how to steal from the office has only been identified as “Participant Five” in court documents.

Two other people, Walters’s niece Jayrece Turnbull and former Tax office employee Diane Gustus, are still awaiting trial. Including Walters, ten people have now pleaded guilty in the conspiracy.