In 1790 he was elected to the magistracy of Montpellier but his national political career began when he was elected to the National Convention on 8 September 1792 for the department of Gard. He was elected seventh out of eight deputies with 288 votes out of a total 486 cast. He maintained a low profile in the Convention, broadly sharing his brother's Girondin views. One of the issues he spoke out on was the contentious question of whether common land should continue to be owned collectively or whether it should be divided up and sold as private property. On 11 October 1792 the Convention passed a decree suspending legislation passed only two months previously and requiring common land to be utilised as it had been traditionally; Rabaut-Pommier urged that a report on the August legislation be made without delay, and the Convention's Agricultural Committee charged him with producing it. The political difficulties of the issue meant that instead of producing clear recommendations, he presented a series of questions on common land which were debated by the Agricultural Committee between 29 December 1792 and 12 January 1793. At the Trial of Louis XVI he voted for the king to be executed, but only after the decrees establishing the new French Republic had been ratified.