If a service member is questioned by a military official in violation of Article 31(b), meaning they were suspected of an offense but not properly advised of their rights, the primary consequence is the suppression of any statement they made. This is the military’s statutory exclusionary rule, a powerful remedy designed to deter misconduct by investigators and protect the rights of the accused.
This rule is explicitly stated in Article 31(d) of the UCMJ, which mandates that no statement obtained from a person in violation of the article “may be received in evidence against him in a trial by court-martial.” This means the prosecution is legally barred from using the illegally obtained confession or admission as evidence to prove the service member’s guilt. The statement is rendered inadmissible.
The consequences can extend beyond the statement itself under the “fruit of the poisonous tree” doctrine. Not only is the initial statement suppressed, but any other evidence that was discovered as a direct result of that illegally obtained statement may also be excluded from trial. For example, if an unlawfully obtained confession leads investigators to the location of a hidden weapon, both the confession and the weapon could be suppressed.
To enforce this, the defense counsel will file a motion to suppress the statement with the military judge. If the judge agrees that an Article 31 violation occurred, the evidence will be excluded. This can be devastating to the government’s case, and if the suppressed statement was the primary evidence of guilt, the violation could lead to the dismissal of the charges.