However, he ultimately decided to become a lawyer, and returned to Baltimore after his father's death to read law under the director of Robert Goodloe Harper.

Latrobe became a lawyer for the Baltimore and Ohio Railroad, initially arranging for land acquisitions (and publishing a work about conveyancing in 1826).

[6] In 1871 he delivered a lecture on the history of the steamboat which explained the contribution of Nicholas Roosevelt, who had married his elder half-sister Lydia Sellon Latrobe.

[10] Latrobe gave a speech about history of the Mason–Dixon line to the Historical Society of Pennsylvania in 1854 which was widely reprinted, and also helped found Druid Hill Park, serving on its board of directors from 1860 until his death.

Latrobe also achieved some distinction as a poet and painter, and was one of the 3-judge panels which awarded Edgar Allan Poe a prize for his "Manuscript in a bottle", which was published in Baltimore's Sunday Visitor paper and helped launch the writer's career.

[13] His son Ferdinand C. Latrobe (1833–1911) became a lawyer and author like his father, served in the Maryland legislature and was elected Baltimore's mayor seven times.