When a service member is suspected of an offense under Article 120 of the UCMJ, 10 U.S.C. 920, investigators frequently seek a DNA sample. DNA can connect a person to an encounter, exclude a person, or corroborate or contradict an account. Because a DNA swab is a search and seizure of the body, the collection is governed by constitutional and military legal protections. A service member under Article 120 suspicion is not without rights during this process, and understanding those rights is important both to protect the individual and to ensure that any evidence obtained is lawful.
DNA Collection Is a Search Under the Fourth Amendment
Taking a DNA sample, typically a buccal swab from the inside of the cheek, is a search subject to Fourth Amendment protection. The Supreme Court addressed cheek-swab DNA collection in Maryland v. King, recognizing it as a search while upholding collection in the context of a booking procedure following an arrest for a serious offense supported by probable cause. In the military, the same constitutional principles apply, filtered through the Military Rules of Evidence governing searches and seizures. The core consequence is that the government generally needs lawful authority to take a sample, and a service member has the right to insist that the proper legal basis exist.
Authorization: Consent, Command Authorization, or Probable Cause
There are several lawful avenues for DNA collection from a suspect. The government may seek the member’s voluntary consent. It may obtain a search authorization, which in the military is the functional equivalent of a warrant, issued by a commander with authority over the place or person or by a military magistrate, based on probable cause. In some circumstances a search may be justified by exigent or other recognized exceptions. A service member has the right to require that one of these lawful bases be present. If a sample is taken without consent and without proper authorization or an applicable exception, the defense can move to suppress the DNA and any evidence derived from it under the Military Rules of Evidence.
The Right to Decline Consent
A suspect is not required to consent to a DNA swab. Consent must be voluntary, and the government cannot obtain valid consent through coercion, deception about the purpose, or the implication that refusal is not an option. Declining to consent is not itself evidence of guilt and cannot be used as a substitute …