Joe McCann was a Staff Captain in the Officials and killed unarmed by the British Army in 1972.
[4][5] Staff captain (Stabskapitän, also: Stabshauptmann) is a historic military rank used in the Prussian army.
Its holder represented the actual captain and company commander in his absence, frequently and often for long periods, should his (usually noble) Hauptmann show no interest in leading the company, though the Hauptmann would retain his rank, status and uniform.
Some exceptions were made to this rule, such as transfer to the executive officers list and promotion to Captain of Sir Frederick Evans upon his retirement in 1872, in recognition of his hydrographic survey work and scientific merits.
Stabshauptmann (StHptm) meaning "Staff Captain", is the highest military rank in the Bundeswehr for limited duty officers (Offiziere des Militärfachlichen Dienstes (OffzMilFD)).
Historically, a rank named "Stabshauptmann" (also: "Stabskapitän") existed in several German armies (such as Prussia) in the 18th century.
To express the seniority of Stabshauptmann, "OF-2a" or other modifications of the official NATO rank code are in use unofficially.