The military does not have a single, formal list that defines a “serious offense” for the purpose of determining eligibility for a punitive separation (a Bad Conduct or Dishonorable Discharge). Instead, the determination is made based on the maximum punishment authorized for the specific offense of which the service member was convicted, as outlined in the Manual for Courts-Martial (MCM).
As a general rule, any offense that is considered a felony in the civilian world or that carries a maximum authorized punishment that includes a Dishonorable Discharge, a Bad Conduct Discharge, or confinement for more than one year is considered a “serious offense.” This includes nearly all drug offenses, larceny, most assaults, all sexual assault offenses, and any offense that shows a grave departure from the standards of military conduct. A special or general court-martial is the only forum that can adjudge a punitive discharge.
A military defense attorney understands this framework. When a client is charged with an offense that authorizes a punitive discharge, the attorney knows that a primary goal of the defense is to avoid that outcome. They will either fight for a full acquittal or, if a conviction is likely, they will negotiate a pretrial agreement that caps the potential punishment and, most importantly, agrees to withdraw and dismiss the punitive discharge. The definition of a “serious offense” is thus tied directly to the maximum punishments authorized in the MCM for that specific crime.