He was elected a deputy of the Constituent Assembly in 1848, served briefly as Minister of the Navy, and became a senator in the Second French Empire in 1852.

When Casy was 10 years old a squadron commanded by Admiral Pierre Martin came to anchor in Golfe-Juan.

[1] In 1805 he served on the frigate Pomone when it took Prince Jérôme Bonaparte to Algiers to reclaim Genovese slaves.

[2] He served under Admiral Julien Cosmao in operations off Barcelona and Tarragona and distinguished himself in the Mediterranean expedition of 1813.

[1] That year he sailed on the Colosse in a group of ships under Rear Admiral Jurien dispatched to establish trade relations with the South American states.

[1] Casy participated in the Spanish Civil War in 1823, blockading the coast of Catalonia on the frigate Junon.

Casy then was made chief of staff to Rear-Admiral Claude Charles Marie du Campe de Rosamel.

[2] Casy took part in the expedition to Greece in 1828 where he assisted in the capture of Navarino, Koroni, Methoni and the forts of the Peloponnese.

Admiral Roussin, commander-in-chief of the Portugal expedition, complimented Casy on his handling of his vessel during the Battle of the Tagus.

[3] From 1837 to 1838 he was captain of the 100-gun Hercule, where he instructed the king's son, François d'Orléans, Prince of Joinville, in naval matters.

[3] After the February Revolution of 1848, Casy ran for election on 23 April 1848 to represent Var, where he was maritime prefect, in the Constituent Assembly.

[1] He became a Grand Officer of the Legion of Honour and vice-chair of the Admiralty Board during the Second French Empire.