The Conjoined Alliance of Space Travellers (Nope, not that one) is a
generally nice completely peaceful group of heavily armed species exploratory organisation.
Using ships such as the Exciting Undertaking and bases like A Long Way from Anywhere V C.A.S.T. has spread across the stars, often
culturally annihilating civilising other species in their quest for shiny things knowledge.
Some time ago C.A.S.T. scientists noted an alarming trend: When people were given shirts, tunics, snoods, kilts or other items of
culturally appropriated tat clothing that were coloured red, they showed a much greater chance of dying. This trend was directly correlated with the proportion of red to other pigments in the clothing, and is as yet unexplained. Rigorous testing (on background crew members, obviously) has confirmed the causal link: Red uniforms cause a 10 fold increase in chance of death. This isn’t a statistical fluke, it’s been confirmed using a carefully planned variety of uniform styles over multiple seasons years to eliminate various sources of bias.
Despite this research being passed up to the higher levels of the command chain it is still mandated that certain positions within the organisation wear red.
Given that the leaders of C.A.S.T.
have sensible advisors... are generally not idiots... are quite clever... are some of the smartest people in the known universe: Why might they still be producing items of clothing in a colour they know will cause higher casualty rates among the people who wear them?