Trespasser ah initio
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
Trespasser from the beginning. A term applied to a tort-feasor whose acts relate back so as to make a previous act, at the time innocent, unlawful; as, if he enter peaceably, and subsequently commit a breach of the peace, his entry is considered a trespass.
Stim Gloss. See Wright v. Marvin, 59 Vt. 437, 9 Atl. 601.