He returned to New Orleans and eventually succeeded to his father's business of compressing cotton for shipment abroad.
Under his direction, the Freret Cotton Press Company became the first large industrial firm in New Orleans, and propelled him to public visibility and a political career.
His meticulous temperament made him one of the most efficient mayors in New Orleans' history; he was a hands-on administrator notorious for his surprise inspections of city facilities, for example.
His term was marked by the continuation of the city's recovery from the combined effects of the borrowing and spending of previous mayors and the nationwide economic crisis of 1837; and hampered by the curious administration he inherited, in which the city was divided into three autonomous — and often acrimoniously competing — "Municipalities".
Despite these difficulties, he succeeded in establishing a free public school system and obtaining backing for it at the state level.