After graduating in 1826, Peck moved to Cincinnati, Ohio, where he clerked in the law office of Bellamy Storer.
[2] He moved to Scioto County, Ohio in 1827, and had a law practice there until 1847.
[2] In 1844, the Whig Ohio General Assembly elected him a Common Pleas Judge.
[3] In 1858, as a Republican, Peck defeated incumbent Democrat Thomas Welles Bartley as Judge on the Ohio Supreme Court.
[2] Peck married Mary Ann Cook on July 8, 1830.