A review of state records published Sunday by the Houston Chronicle showed that during Perry's nine years in office chief executives in other death penalty states granted clemency for humanitarian reasons at least 200 times -- including 171 in Illinois, where questions of innocence were present.
The newspaper said that while Texas under Perry has executed 200 inmates, only once has the governor spared a condemned man's life when he wasn't forced to by the U.S. Supreme Court.
The Chronicle said at least 50 of the past 200 Texas executions were carried out without any clemency board review.
The newspaper's analysis comes as Perry has endured criticism for a quick dismissal of a clemency request from Cameron Todd Willingham, executed in 2004 for the deaths of his three daughters. Advocates say documents faxed to Perry 88 minutes before the execution cast doubt on Willingham's guilt, but the governor has refused to release records to indicate whether he read them.