After the July Revolution of 1830 he came to Paris, formed connections with numerous political figures, even with King Louis Philippe, and became a brilliant defender of Liberal ideas in the law courts and in the press.

Examples include his Éloge funèbre of the bishop Grégoire (1830), his Mémoire for the political rehabilitation of Marshal Ney (1833), and his plea for the accused of April 1835.

On 24 February 1848 he was chosen by the Republicans as a member of the provisional government, and as minister of justice he secured the decrees abolishing the death penalty for political offenses, and making the office of judge immovable.

[citation needed] When the conflict between the Republicans and Socialists broke out, he resigned office but continued to sit in the constituent assembly.

[3] While in the government of the national defence, he secured full citizenship for the Jews in French-ruled Algeria, through the Crémieux Decree (décret no 136 du 24 octobre 1870).

The decree allowed for native Jews to become French citizens while Muslim Arabs and Berbers were excluded and remained under the second-class ‘indigenous’ status outlined in the Code de l'Indigénat.

A street is named after him in Jerusalem's German Colony neighborhood,[2] as well as in central Tel Aviv and the French Carmel district in Haifa.