Another set of radical changes introduced by the Committee of Detail proved far more contentious when the committee's report was presented to the convention. On the day the convention had agreed to appoint the committee, Southerner Charles Cotesworth Pinckney of South Carolina, had warned of dire consequences should the committee fail to include protections for slavery in the Southern states, or allow for taxing of Southern agricultural exports. In response to Pinckney and his fellow Southern delegates, the committee had included three provisions that explicitly restricted the Congress' authority in ways favorable to Southern interests. The proposed language would bar the Congress from ever interfering with the slave trade. It would also prohibit taxation of exports, and would require that any legislation concerning regulation of foreign commerce through tariffs or quotas (that is, any laws akin to England's "Navigation Acts") pass only with two-thirds majorities of both houses of Congress. While much of the rest of the committee's report would be accepted without serious challenge on the Convention floor, these last three proposals provoked outrage from Northern delegates and slavery opponents.