Historians have long assumed Tresham penned the letter, although this theory has yet to be verified. Catesby and Wintour were both suspicious of him and threatened to kill him, but he was able to persuade them differently. On December 23, 1605, he died of natural causes. He was buried on Christmas Day at Holy Trinity Church in London. Tresham had many enemies, including some within the family itself. His wife had inherited money from her father and some believe she tried to replace Wintour with another sister as leader of the movement. There are also stories that she had an affair with Catesby and when he found out he had a violent reaction against her. She was imprisoned for a while but was later released. After Tresham's death, Thomas Wintour became the new leader of the movement. In April 1606, he wrote a letter to King James I accusing Catesby of planning to blow up Parliament during the state opening on May 5. The letter caused Catesby to become a suspect in the eyes of the law and he was arrested along with Tom Ward. They were all found guilty of treason and sentenced to die. However, due to lack of evidence against them, their sentences were commuted to imprisonment.