Illinois Man Arrested for Mailing Powder to Four Congress Members

The case illustrates a recurring vulnerability in threatening-mail prosecutions: senders who include identifying information on envelopes, which has accelerated law enforcement timelines in...

Matthew Unglesbee, 36, of Quincy, Illinois, was arrested and remained in the custody of U.S. Marshals as of Tuesday after federal authorities alleged he mailed letters containing suspicious white powder to four members of Congress, according to an eight-page criminal complaint unsealed Monday in federal court.

Unglesbee faces two federal charges: perpetrating a hoax and sending threatening communications through the mail, according to the criminal complaint cited by The Guardian. No specific penalty range has been publicly cited in available court documents, but federal law under 18 U.S.C. Section 1038 provides for imprisonment of up to five years for conveying false information about a biological weapon, and up to five additional years if the conduct results in serious bodily injury.

The criminal complaint, signed by Charis Hobbs, a task force agent involved in the investigation, states that Unglesbee allegedly wrote his own name and return address on the envelopes before mailing them. That detail allowed investigators to identify and locate him without a prolonged search, according to the complaint. The Guardian reported the complaint runs eight pages.

The four members of Congress who received the letters have not been publicly identified in the available court record, and it is unknown which chamber or party affiliations they represent. The document or subsequent court filing that would name the recipients is the criminal complaint itself, which was unsealed Monday but whose full contents have not been reproduced in available public reporting as of publication time.

Authorities have not publicly confirmed the composition of the powder. Whether it was a controlled substance, a biological agent, or an inert material is not established in available source material. A laboratory analysis report, if filed with the court, would be the document that answers that question.

The U.S. Capitol Police, the FBI, and the U.S. Postal Inspection Service routinely share jurisdiction over mail-based threats to members of Congress. Which agency led this investigation has not been specified in available reports. The task force structure referenced in the complaint suggests a multi-agency effort, which is standard procedure under Capitol Police protocols for congressional mail threats.

Federal law enforcement agencies have processed suspicious mail incidents directed at Congress members with regularity since the 2001 anthrax letter attacks, which killed five people and infected 17 others. That episode prompted the construction of a dedicated mail irradiation and screening facility in Landover, Maryland, which processes congressional mail before delivery. Whether the letters in this case passed through that facility or were delivered through another route is not established in available source material.

Sending threatening communications through the U.S. Mail to a federal official is a separate offense under 18 U.S.C. Section 876, which carries a maximum of 10 years imprisonment when directed at federal officials. Whether prosecutors will pursue that statute in addition to the hoax charge is not stated in available court records. The charging document would reflect any superseding indictment if one is filed.

Unglesbee's attorney, if one has been appointed or retained, has not been identified in available reporting. No statement from the defendant or defense counsel appeared in source material reviewed for this article.

The case remains at the arrest and complaint stage. A preliminary hearing or arraignment date has not been publicly reported. The full eight-page criminal complaint, available through the relevant federal district court's public access to court electronic records (PACER) filing, would contain the complete factual basis for the charges, the identities of the targeted Congress members, and the specific language of any communications included with the powder.