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Dangerous Mail Investigations
The objective of the Dangerous Mail Investigations Program is to protect the U.S. Postal Service, secure the nation’s mail system and ensure public trust in the mail. This is accomplished through public awareness, prevention efforts, and the aggressive investigation of individuals who violate federal laws and Postal Service rules and regulations.

Specially trained and equipped Postal Inspectors within the Dangerous Mail Investigations (DMI) Program respond when a prohibited mailing, mail bomb or substance may cause harm to Postal Service employees, Postal Service customers, the mail, or Postal Service property. These DMI Inspectors use a variety of screening equipment to determine whether or not the suspicious substances and/or items pose a threat to Postal Service employees or the general public. Refer to the SUSPICIOUS MAIL poster and the DOMESTIC MAIL MANUAL for mailability regulations.

Suspicious Substance/Item Response
Postal Inspectors within the DMI Program respond on a daily basis to postal facilities, businesses and customers when suspicious substances (whether unknown powders or liquids) are reported that may be associated with the mail or mail processing equipment. Using an array of specialized screening equipment Postal Inspectors are able to determine whether these unknown powders or liquids pose a threat to postal infrastructure, its employees or the general public. In 2013, Postal Inspectors investigated three separate cases involving individuals mailing Ricin, a deadly toxin, via the US Mail. Three individuals were arrested and prosecuted in those investigations.

In addition to suspicious substance response, Postal Inspectors respond to suspicious items associated with the US Mail. A suspicious item could be classified as an item which may or may not contain an Improvised Explosive Device (IED). Using portable X-Ray equipment, Postal Inspectors are able to determine whether or not a suspicious item contains an IED or other classes of prohibited mailings. In 2018, Postal Inspectors assisted other federal law enforcement agencies with a case involving the placement of various IED packages throughout Austin, TX. Although the packages were not sent via the US Mail, Postal inspectors assisted in this multi-agency investigation. Unfortunately, these devices resulted in several deaths and injuries. Using various investigative techniques, the responsible individual was subsequently identified.

Extortion and Threats
Postal Inspectors investigate individuals who use the mail to extort money or assets from victims by threatening to injure their reputation or accusing them of a crime. In addition, Postal Inspectors investigate individuals who use the mail to threaten physical harm to victims. The Code of Federal Regulations (30 CFR 233.11) provides the Chief Postal Inspector with the authority to screen mail reasonably suspected of being dangerous to a person or property.

Mail Screening Program
The Code of Federal Regulations (30 CFR 233.11) provides the Chief Postal Inspector with the authority to screen mail reasonably suspected of being dangerous to a person or property.

Postal Inspectors are often called upon to use multi-tiered field-screening tools in order screen mail during high profile events. Working alongside law enforcement partners, the work Postal Inspectors provide conveys an “envelope of safety” by protecting mail delivered to high-profile venues, designated as at National Special Security Events. Such events include the Olympics, Super Bowl, or other large-scale events where terroristic threats are possible.

In the wake of the biological attacks of 2001, the U.S. Postal Service installed the Biological Detection Systems (BDS) to safeguard postal employees and the public from future incidents. BDS serves as an early warning system for the presence of dangerous biologicals. Since the inception of BDS, there have been well over 7 million tests, but not one positive or false-positive result.

DMI Inspectors regularly participate in drills with federal, state, and local partners to test response protocols in the event BDS detects a dangerous substance. Due to the vigilance of the U.S. Postal Inspection Service, the U.S. Mail continues to be one of the safest forms of communications in the world.

3 Postal Inspectors in HAZWOPER suits

U.S. Postal Inspectors enforce more than 200 federal laws through investigations of crimes that may adversely affect the U.S. Mail or postal customers. Several of these laws relate to prohibited mailings, extortion and threats:

The enforcement responsibilities under 18 U.S.C. 841-848 are shared by the Bureau of Alcohol, Tobacco, Firearms, and Explosives; the Federal Bureau of Investigation (FBI); and the Postal Inspection Service. The Postal Inspection Service has primary investigative jurisdiction for violation of these sections as they relate to the mail and Postal Service property.

Related jurisdiction
18 U.S.C. 876
18 U.S.C. 1715
18 U.S.C. 1716
18 U.S.C.1038

Postal Inspectors loading mail into vehicle

Call U.S. Postal Inspectors for help with buzzing, ticking parcels; mailed suspicious substances, or mailed threats at 1-877-876-2455 (option 2)