Scott Panetti handwritten envelope with 10 lines penned by him from 2004
Panetti v. Quarterman, 551 U.S. 930 (2007), is a decision of the Supreme Court of the United States of America, ruling that criminal defendants sentenced to death may not be executed if they do not understand the reason for their imminent execution, and that once the state has set an execution date death-row inmates may litigate their competency to be executed in habeas corpus proceedings.