In 1849 Theophilus [Theophile in French] LaChapelle was a handsome man thought to have a brilliant mind. He was a lawyer and had served in the Wisconsin Territorial Legislature, representing Crawford County. Theophilus was born in 1813, probably at Prairie du Chien. His father was Antoine LaChapelle and his mother, Pelagie, was a daughter of Pierre LaPointe, a valuable Indian interpreter from Canada and a Dakota woman, whose father was the first of the chiefs called Wabasha. The attorney had a number of brothers and sisters. One of these last, Therese, married Bernard W. Brisbois, son of Prairie du Chien fur trader, Michel Brisbois, and Madeleine Gautier de Verville. Another half sister, [father being an Englishman named Crawford] Sophia Mitchell, was a celebrated beauty whose death at a young age affected Theophilius badly.
Suddenly—or so it seemed—Theophilus LaChapelle lost his reason. A good many people were shocked to find out that the learned young man was accused of murdering Louis Menard and burning down his house. A newspaper reported that the lawyer had set fire to the upper story and, as Menard ascended a ladder to put it out, LaChapelle fired two shots into his head. He also attempted to prevent others from going to the aid of the mortally wounded man with his weapon but was overcome. Theophilus was tried and acquitted by reason of insanity. Some believed his mind had become unbalanced from too much studying—or perhaps that was an excuse thought up by his lawyer. LaChapelle became a ward of his brother-in-law, B. W. Brisbois, and when the Mendota State Hospital opened in Madison in 1860, the man who had destroyed his own life in addition to that of a perceived enemy, was transferred there and remained for the rest of his days. Where LaChapelle had spent the preceeding ten years I do not know, nor do I know what he had against Louis Menard [spelled "Maynard" in some reports].