Definition
A Latin phrase meaning "going, remaining, and returning." The phrase describes the full scope of a privilege from arrest granted to certain persons — protection that attaches not only during the principal occasion itself but also while traveling to it, while present at it, and while traveling back from it. The privilege extends across the entire journey and stay, not merely the moment of the protected activity.
The phrase most commonly appears in the context of legislative privilege from arrest. Members of a legislature, parties to legal proceedings, and others entitled to immunity from civil arrest have historically been protected during all three phases captured by the phrase: the journey to the protected engagement (eundo), the time spent there (morando), and the return home (redeundo).
Common Confusion
The phrase is sometimes loosely cited as if the privilege it describes is absolute and perpetual. It is neither. The privilege covers a specific occasion and a reasonable travel period connected to that occasion. Courts applied a reasonableness standard to the duration and route, and the privilege did not attach to all arrests — historically it generally ran only against civil, not criminal, process.
Why It Matters in Research
The phrase is a term of art that does not appear in isolation — it functions as a modifier explaining the temporal and geographic scope of privilege claims. When encountered in historical pleadings, court opinions, or legislative privilege disputes, it signals that the speaker is invoking the full-journey rule rather than a narrower point-in-time protection.
Researchers working with pre-twentieth century American and English materials will encounter this phrase most often in civil arrest contexts. Civil arrest as a remedy for debt was abolished or severely curtailed across most American jurisdictions during the nineteenth century, which reduced but did not eliminate the phrase's practical relevance. The privilege survived in legislative and judicial attendance contexts well after civil arrest faded.
A research trap: Bouvier's entry uses the variant "undo" in its heading, which appears to be a typographical corruption of "eundo" — the standard Latin term. Researchers searching historical indexes or digitized sources may need to search under both spellings. The phrase itself is sometimes rendered with variations in spacing or hyphenation across different editions and reporters.
The phrase also appears in English common law materials concerning parliamentary privilege and the privilege of suitors and witnesses attending court. Researchers moving between American and English historical sources should note that the underlying privilege rules, while parallel in structure, developed on somewhat different tracks and were not identical in scope.
Historical Dictionary Support
Bouvier's is the primary shelf source for this phrase in the American tradition, and its treatment is characteristically compact. The entry correctly identifies the three components of the Latin phrase and correctly ties them to the privilege from arrest doctrine. Bouvier does not elaborate on the limits of the privilege — for instance, whether a detour for personal business breaks the protected journey — nor does it address the privilege in the legislative as distinct from the civil litigation context.
The phrase appears in English legal dictionaries of the same era in similar form. What the historical dictionary entries collectively miss is any discussion of how courts actually adjudicated the boundaries of the protection: what counted as an unreasonable deviation from the route, how long "morando" could extend, and whether the privilege covered criminal as well as civil process. These questions were addressed in case law rather than in the dictionaries, so researchers should treat the dictionary treatment as a starting definition only.