 Pearre was elected to the Maryland State Senate in 1890, and served until 1892.He was prosecuting attorney of Allegany County, Maryland, from 1895 to 1899, and was elected as a Republican to the Fifty-sixth and to the five succeeding Congresses, serving from March 4, 1899 to March 3, 1911.He declined to be a candidate for reelection in 1910 to the Sixty-second Congress, and engaged in the practice of his profession until his death in Cumberland.