Yes, new charges can be added after an Article 32 preliminary hearing concludes, but doing so requires additional procedural steps. The government is not permanently locked into the set of charges that were the subject of the initial hearing. If new evidence comes to light or the command decides to pursue additional offenses, they can prefer and add new charges to the case.
However, if these new charges are to be referred to a general court-martial along with the original ones, the accused generally has the right to another Article 32 hearing on those new charges. The accused cannot be forced to face a new major offense at a general court-martial without the benefit of a preliminary hearing on that specific offense. This ensures that the same procedural safeguards apply to all charges being considered for the highest level of military trial.
The accused can choose to waive their right to a second Article 32 hearing on the new charges. This might happen for strategic reasons, such as to expedite the case or as part of ongoing plea negotiations. The decision to waive would be made in consultation with defense counsel.
Alternatively, the convening authority might choose to refer the new charges to a lower forum, such as a special court-martial, which does not require a preliminary hearing. In this scenario, the accused could face two separate trials or the cases could be consolidated, depending on the circumstances. The key principle is that the right to an Article 32 hearing attaches to the charges being considered for a general court-martial, and the government cannot circumvent this right simply by adding charges after the initial hearing is complete.