Potentially dangerous taxpayer

Potentially Dangerous Taxpayer (PDT) is a government designation assigned by the Internal Revenue Service (IRS) to taxpayers of the United States of America whom IRS officials claim have demonstrated a capacity for violence against employees of the IRS or other government agencies, contractors or their families. Suspected PDT cases are handled by the Treasury Inspector General for Tax Administration.

Source: Wikipedia — Potentially dangerous taxpayer (CC BY-SA 4.0)