In 1859 his listing in the Wisconsin Blue Book describes him as a farmer; he was the youngest member of the Senate, at age 28, and was assigned to the standing committees on militia and on engrossed bills.[2] In 1860, he was succeeded by Michael Egan, another Democrat born in Ireland.
He was elected to the Assembly's 9th Milwaukee County district (the Towns of Franklin, Greenfield, Lake, and Oak Creek) for 1868, succeeding fellow Democrat Valentin Knœll. He showed his postal address as "Hill's Corners" (presumably Hales Corners in the Town of Greenfield) and still listed himself as a farmer. He was assigned to the committees on state affairs, and on education.[3]
He was succeeded for 1869 by Henry Roethe, also a Democrat.
His wife Mary Ann died at the age of 21 in 1859. Walsh apparently did not remarry and is buried with Mary Ann at the Saint Marys Cemetery in Hales Corners.
