Born in Lynn, Massachusetts, Alley attended the common schools. At the age of fourteen was apprenticed as a shoemaker, but was released at nineteen. He moved to Cincinnati, Ohio, in 1836. Freighted merchandise up and down the Mississippi River. He moved to Lynn, Massachusetts, in 1838 and entered the shoe manufacturing business. He established a hide and leather house in Boston in 1847. He served as member of the first board of aldermen of Lynn in 1850. He served as member of the Governor's council 1847-1851. He served in the State senate in 1852. He served as member of the constitutional convention of 1853.
Alley was elected as a Republican to the Thirty-sixth and to the three succeeding Congresses (March 4, 1859-March 3, 1867). He served as chairman of the Committee on the Post Office and Post Roads (Thirty-eighth and Thirty-ninth Congresses). He was not a candidate for renomination in 1866. He became connected with the Union Pacific Railroad. Abandoned active business pursuits in 1886 and lived in retirement until his death in West Newton, Massachusetts, January 19, 1896. He was interred in Pine Grove Cemetery, Lynn, Massachusetts.
