After serving without a salary as the Professor of Rhetoric and Belles Lettres at the University of Maryland, Pinkney traveled to Mexico with the intention of joining the navy there. Disheartened after not being able to join, he returned to Baltimore. There, he became editor of a new semiweekly newspaper the "Marylander"—a publication founded to support the re-election of John Quincy Adams. Its first issue was published December 3, 1827. His editorial association nearly brought him into a duel with the editor of Philadelphia-based "Mercury", a publication which supported Andrew Jackson. Afflicted with depression, Pinkney died on April 11, 1828, at the age of 25. He was originally buried in Baltimore's Unitarian Cemetery but, in May 1872, his body was moved to Green Mount Cemetery.