Many people confuse the terms, AWOL and Desertion. Some people believe that AWOL is when someone is absent for less than 30 days, and someone absent from the military for 30 days or more is a deserter. That's not quite true.
Unauthorized absence from the military fall under three articles of the Uniform Code of Military Justice (UCMJ): Article 85, Desertion, Article 86, AWOL, and Article 87, Missing Movement. Of the three, Desertion is the most serious offense.
A military member has violated Article 87 if he/she is ordered to be on a ship or an aircraft, or deploy with a unit on a certain date and time, and then fails to show up. It doesn't matter if the member failed to show up through intention or because of neglect, but it is required that the member knew about the movement. A viable defense would be that the member missed the movement through physical inability (as long as that physical inability wasn't a result of misconduct or neglect). The possible punishment is more severe if the member missed the movement on purpose. It's not uncommon for Missing Movement to be charged in conjunction with AWOL or Desertion, depending on the circumstances.
AWOL, or "Absent without Leave," is usually called "Unauthorized Absence" (or UA) by the Navy and Marine Corps, and AWOL by the Army and Air Force. The use of "UA" by the Navy/Marine Corps and "AWOL" by the Army/Air Force is historical. Prior to enactment of the Uniform Code of Military Justice in 1951 the services were governed by separate laws. However, its official title under the current UCMJ is "AWOL" (a rose by any other name is still a rose). It simply means not being where you are supposed to be at the time you are supposed to be there. Being late for work is a violation of Article 86. Missing a medical appointment is a violation. So is disappearing for several days (or months, or years). The maximum possible punishments, which I'll discuss later in this article, depends on the exact circumstances of the absence.
Did you know that desertion can result in the death penalty? It's true. The maximum punishment for desertion during "time of war" is death. However, since the Civil War, only one American servicemember has ever been executed for desertion -- Private Eddie Slovik in 1945.
The offense of desertion, under Article 85 carries a much greater punishment than the offense of AWOL, under Article 86. Many people believe that if one is absent without authority for 30 days or more, the offense changes from AWOL to desertion, but that's not quite true.
The primary difference between the two offenses is "intent to remain away permanently," or if the purpose of the absence is to shirk "important duty," (such as a combat deployment).
If one intends to return to "military control" someday, one is guilty of AWOL, not desertion, even if they were away for 50 years. Conversely, if a person was absent for just one minute, and then captured, he could be convicted of desertion, if the prosecution could prove that the member intended to remain away from the military permanently.
If the intent of the absence was to "shirk important duty," such as a combat deployment, then the "intent to remain away permanently" to support a charge of desertion is not necessary. However, Such services as drill, target practice, maneuvers, and practice marches are not ordinarily "important duty." "Important duty" may include such duty as hazardous duty, duty in a combat zone, certain ship deployments, etc. Whether a duty is hazardous or a service is important depends upon the circumstances of the particular case, and is a question of fact for the court-martial to decide.
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