Habeas corpus is a legal term of art that requires a government to show justification for the imprisonment of a person. Basically, it means that we can't imprison people without cause. Because this involves holding people in prison, it makes sense that the Latin phrase literally translates into "have the body" (or, in plural, habeas corpora). This refers to the person in custody and not an actual body as proof, as some people mistakenly believe. Habeas, through Proto-Italic habeo, comes from the Proto-Indo-European reconstruction gehb, meaning "to take" (also the etymon of Modern English have, through Old English hafian and Proto-Germanic habjana, "to lift"). Corpus, as one may imagine, is the progenitor of corpse (through Old French cors) and corps (through French corps d'armee, "army body"). This is reconstructed to Proto-Indo-European krep, also meaning "body", with a brief pit stop in Proto-Italic.
Adam Aleksic, a leading contender for valedictorian of his high school, is a 211-month-old boy with disturbing interests in etymology, vexillology, geography, and law. Adam would like to one day visit Tajikistan and probably isn't spying for the Kyrgyz government.
The Etymology Nerd