Yes, a victim’s refusal to cooperate can, and often does, result in the dismissal of an Article 120 (sexual assault) charge, but it is not automatic. The decision rests with the prosecutor (the trial counsel) and the commander. A sexual assault case is prosecuted by the government on behalf of the United States, not by the victim. Therefore, the government can technically proceed with the case even if the victim does not want them to.
However, in many Article 120 cases, the victim’s testimony is the most critical, and sometimes the only, evidence of the offense. If the victim refuses to testify at the court-martial, the prosecutor is left with a very weak case. They may try to proceed using the victim’s prior out-of-court statements to investigators, but this is subject to strong hearsay objections from the defense attorney and violates the accused’s constitutional right to confront their accuser.
A military defense attorney in this situation would file a motion to dismiss the charges for lack of evidence. The prosecutor, realizing they cannot prove their case beyond a reasonable doubt without their key witness, will often be forced to agree. The command will then typically withdraw and dismiss the charges. While the government has the power to try and compel a military victim to testify, they are often reluctant to do so, and a victim’s refusal to cooperate is one of the most common reasons that sexual assault charges are ultimately dismissed.