The Potentially Dangerous Taxpayer Flag: How the IRS Marks Accounts for Employee Safety

Frustration with the IRS is normal. Threatening an IRS employee is something else, and the IRS has a formal program for it. An account can be marked Potentially Dangerous Taxpayer, PDT, or Caution Upon Contact, CAU. The flag follows the account across IRS systems for years.

Most people will never be anywhere near this. But it is worth understanding, because a single angry moment in a stressful case can have long consequences.

Where the program came from

IRM 25.4.1.1.1 (rev. 2025-03-21) gives the history. In 1984 the IRS Commissioner assigned IRS Inspection to develop a program to identify taxpayers who represent a potential danger to employees. Inspection became the Treasury Inspector General for Tax Administration in 1999, and the PDT program moved there, but the IRS later took administration back and established the Office of Employee Protection in February 2000 to run it. TIGTA kept its investigative role.

Today, under IRM 25.4.1.1.3, TIGTA reviews incidents, opens PDT cases, investigates and sends a report of investigation to the Office of Employee Protection. That office decides whether the criteria are met and inputs or removes the indicator on IRS systems.

The criteria

IRM 25.4.1.2 says a PDT designation must be based on verifiable evidence or information and must have a nexus to tax administration. The behavior must have occurred within the ten years before classification. The criteria include individuals who:

• Physically assaulted an IRS employee, former employee or contractor, or an immediate family member of one.
• Intimidated or threatened such a person through specific threats of bodily harm, a show of weapons, the use of animals or specific threatening behavior such as stalking.
• Were members of or affiliated with groups that advocate violence against IRS employees, or themselves advocated such violence, where it could reasonably be understood to threaten employees or impede their duties.
• Committed those acts against employees or contractors of other government agencies.
• Otherwise demonstrated a propensity for violence.

The IRM adds that association with a PDT, or membership in a group some of whose members advocate violent protest, does not by itself meet the criteria. It also says borderline cases should be resolved in favor of the designation, erring on the side of caution for employee protection.

The nexus requirement is broad too. IRM 25.4.1.1.5 defines nexus to tax administration as having open activity, or a reasonable prospect of future activity, on the taxpayer's or their business's account, or initiating contact with the IRS or another tax administration authority even without open activity. In practice, almost anyone in an active collection case has the nexus.

IRM 25.4.1.1.5 defines threat broadly. It includes a verbal or written expression of intent to harm an employee, contractor or family member, and preventing an employee from leaving a taxpayer's business or residence, even without physical contact.

Caution Upon Contact

There is a lower tier. IRM 25.4.1.6 says that if a referred case meets Caution Upon Contact criteria rather than PDT criteria, the Office of Employee Protection makes a no PDT determination, closes the PDT case and opens a CAU case, and the chief of the office makes the CAU determination. The CAU program has its own IRM section, IRM 25.4.2.

Either indicator tells employees to take care. As I describe in Revenue Officer Initial Contact, IRM 5.1.10.2 (rev. 2025-04-24) tells Revenue Officers to be alert for PDT or CAU codes during pre-contact preparation and, where there is a safety indicator, to consider an armed escort or have the taxpayer meet in the office.

Employees must report incidents

The program depends on reporting. IRM 25.4.1.3 says employees will promptly report assaults, threats, harassment or forcible interference incurred during or related to their official duties to their local Treasury Inspector General for Tax Administration office. They are told to report even if the information does not meet the established criteria, if they believe a threat exists, and to report information about dangerous individuals with relevance to tax administration even when no incident involved an IRS employee.

That is consistent with IRM 5.1.10.6.1, which lists contacting the manager and TIGTA among the steps an officer takes after an assault in the field, and with TIGTA's own complaint categories for IRS employees who were assaulted because of their duties. I describe TIGTA's broader role in TIGTA: The Inspector General That Audits the IRS.

The definitions matter here. IRM 25.4.1.1.5 defines assault as direct physical contact with intent to cause harm, including striking or attempting to strike with objects or brandishing a weapon, and defines intimidate as action intended to make an employee timid or to force or deter them from taking actions. Telling a Revenue Officer you will appeal is not intimidation. Telling them they will regret it if they levy might be read very differently.

Where the flag shows up

Exhibit 25.4.1-1 lists the systems and documents where the PDT indicator appears once designated. They include IDRS transcripts and tax, entity and summary modules, balance due and return delinquency accounts, Corporate Files On-Line modules, the Integrated Collection System screens, ACS Web and examination control systems, among others.

In other words, nearly every IRS employee who pulls up the account will see it. IRM 25.4.1.5 says employees who see the indicator and do not know why can look up the criteria met in the Office of Employee Protection's database.

Representatives are covered too. IRM 25.4.1.7 says an employee assigned a case with a power of attorney has a business need to know whether the representative is designated PDT or CAU, and can check.

How long it lasts

IRM 25.4.1.8 says a PDT indicator stays on the account for five years and is then reevaluated. It is renewed for another five years if any of these apply: another PDT referral was made during the period, the original offense was a physical assault on an employee or contractor, there was an arrest for a threat or assault on an employee or contractor during the period, or there is current IRS activity at the time of review. Otherwise the indicator is removed.

Read the last renewal condition carefully. If you still have open IRS business when the five years are up, the flag can stay.

Who decides, and who can appeal

IRM 25.4.1.4 says the Chief of the Office of Employee Protection makes all PDT determinations. The appeal path described there runs the other way from what taxpayers might expect: when a case is found not to meet the criteria, the referring employee's manager, or for TIGTA-initiated cases the TIGTA Special Agent in Charge, can appeal, with final decisions by IRS General Legal Services.

The IRM section does not describe a taxpayer appeal of a PDT designation.

What it changes in your case

A safety indicator changes logistics. Meetings move to IRS offices. A second employee or an escort may be present. IRM 1.4.50.10.5 (rev. 2025-04-01) says cases with a PDT or CAU indicator should not be assigned to Field Collection's office-based tax examiners. Some third party rules mention it too: IRM 25.27.1.3.4 says a PDT indicator alone is not a sufficient basis for finding that a third party contact notice could lead to reprisal.

The real point is simpler. Every collection case is stressful, and the people on the other side are doing a job. You can disagree firmly, demand that the IRM be followed and escalate to a manager without ever saying a word that sounds like a threat. Calm documentation wins cases. A PDT flag never helps one.