[2] In 1844 Brown was one of the leaders in Grant County to the movement opposing the first proposed Wisconsin Constitution, because it allowed resident aliens to vote.
[3] After serving as a Representative from Grant County in the 4th and 5th sessions of the Legislative Assembly of the Wisconsin Territory in 1846 and 1847 (he was an unsuccessful nominee for Speaker in the latter session),[4] Brown was elected to the first Assembly in early 1848 as a Whig,[5] to represent the Grant County district which included the districts of Hurricane, New Lisbon, Pleasant Valley, Potosi and Waterloo.
[6] At the end of his third term he chose not to seek re-election[citation needed] and declined any further runs for legislative office, instead returning to his law practice in Jackson.
In 1876 Brown was elected the probate judge of Amador County, an office he filled for five years before once again returning to the private practice of law.
[2] Brown retired from practice in 1897, having made extensive investments in local real estate, to the management of which he devoted his time well into the subsequent century.