This answer discusses how combat and non-combat officers fit into a military hierarchy, how this impacts the ability of one to command the other, and how that fits into the ST:TOS hierarchy.

However, at least at two separate times (in Voyager; possibly elsewhere as well) it is stated that in medical matters, the chief medical officer outranks the captain of the ship. That's Starfleet Medical Protocol regulation 121 section A.

  • When is that protocol first established and/or stated, in-universe? (Comparisons to real world situations are welcome as well, but are not the focus of this question.)
  • What are the specific limits to this protocol? Is it, for example, possible for a properly skilled physician to outrank an admiral?
  • 6
    A medical officer does not outrank the line officer in a tradional sense. They have the specific ability to remove them from the chain of command via medical reasons. They cannot give or countermand orders.
    – Jim Green
    Apr 29, 2015 at 13:31
  • @JimGreen: This is an excellent comment and should be elevated to answer if someone can cite in-universe evidence or even real-world precedent. Apr 29, 2015 at 14:06
  • Possible useful background for those without military knowledge: en.wikipedia.org/wiki/Line_officer -- Rank and authority can be impacted by the situation.
    – K-H-W
    Apr 29, 2015 at 14:49
  • My understanding of USN Naval rules is a medical officer (or other officer) cannot relieve a commanding officer. However they can advise the Executive Officer who can relieve the CO (or more usually except in emergencies, request the CO be relieved by a superior). see : doni.documentservices.dla.mil/US%20Navy%20Regulations/…
    – WOPR
    Sep 2, 2015 at 10:22

1 Answer 1


In Star Trek, a lot of the regulations quoted are throw away references. Many of them never occur again, even if they probably should. It's one of the problems with episodic television with different script writers.

That said, the authority of an medical officer to relieve an officer of duty is a significant plot element in the TOS episode The Doomsday Machine. In that instance, the regulation cited is Starfleet Order 104, Section C. Starfleet Order 104 relates to flag officers taking command of a ship, and Section C specifically covers medical officers relieving flag officers of that authority.

Based on conversations with friends and family who have served, in the real world, there are a few different kinds of authority that can potentially interleave in interesting ways. The precise regulations vary from country to country, and sometimes even within the same country (US Army protocols are similar, but not identical to US Navy protocols), so I've abstained from providing links to any single nation's regulations. Instead, I'll cover it in broad strokes.

General authority derives from oaths of office, law, rank structure, traditions and regulations. For example, this authority gives a soldier the right (and obligation) to stop a fight between fellow soldiers, regardless of unit membership. It even applies when you're off duty and out of uniform; it allows one soldier to tell another soldier "Hey, fix your uniform, it's out of regulation." In effect, the authority doesn't come from the individual soldier, but from the regulations they've all sworn to obey.

Command authority is based on your rank and assignment. This is the authority that creates the "chain of command". Orders from superiors flow down this chain; in the civilian world, this is your boss and your bosses' boss and so forth. Orders related to your job but from outside of your chain of command are not legitimate orders. The exact protocols and traditions vary from military to military, of course.

Positional authority is derived from your job, but it also exists and extends outside of the chain of command. This the means by which a medical officer can relieve a superior of duty. The skill set of a medical officer gives him training and knowledge that supersedes that of the non-medical officer; regulations are written to provide him the legal right to use that training in the performance of his duties. This is also the authority that permits enlisted Military Police soldiers to arrest officers and ignore any order that officer may issue to the contrary. Likewise, it gives a military sentry the authority to issue orders to anybody crossing his line of responsibility, again regardless of rank.

  • 4
    Can you link to your sources? References are always a plus.
    – Joe L.
    Apr 29, 2015 at 14:48
  • 1
    The source for the military stuff is conversations over the years with people who have served (I've added a reference to such). Seeing as the subject matter is a fictional universe, and the source traditions are varied, I figured it was better to mention it in broad conceptual strokes, rather than nailing it down with one country or organization's rules.
    – T.J.L.
    Apr 29, 2015 at 15:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.