He felt that they were written by the free state delegates, did not protect the rights of slave owners in the territories, and would do little to bring back the lower South and restore the Union. He voted against the conference's seven resolutions, which the conference sent to Congress for approval late in February 1861 as a proposed Constitutional amendment.
On the same day, the Peace Conference started, local voters elected Tyler to the Virginia Secession Convention. He presided over the opening session on February 13, 1861, while the Peace Conference was still underway. Tyler abandoned hope of compromise and saw secession as the only option, predicting that a clean split of all Southern states would not result in war.[172] In mid-March he spoke against the Peace Conference resolutions, and on April 4 he voted for secession even when the convention rejected it. On April 17, after the attack on Fort Sumter and Lincoln's call for troops, Tyler voted with the new majority for secession. He headed a committee that negotiated the terms for Virginia's entry into the Confederate States of America and helped set the pay rate for military officers. 