Since Rick Perry declared his candidacy for the Republican presidential nomination last week, much ink has been spilled over the controversy surrounding his decision as governor to execute Cameron Todd Willingham—a man whose innocence was advocated by many investigative reports, including a popular investigation by David Grann in The New Yorker. But with 234 executions and counting under Perry’s belt, Willingham hardly represents the only figure whose case and subsequent execution has became the subject of controversy. Here’s a list of the top five most questionable cases beyond that of Willingham.

Humberto Garcia. In July, Texas executed Mexican national Humberto Garcia, despite the fact that he had been denied his right to assistance from the Mexican consulate—a move which many legal experts worried was a violation of international law. Some also feared for the safety of Americans abroad if Mexico decides to retaliate by no longer abiding by the UN treaty granting right to consulate assistance. Garcia had been convicted of the 1996 rape and murder of a 16-year-old girl. The Obama administration petitioned the Supreme Court to grant a stay of execution, but the Supreme Court rejected the request in a 5-4 decision. (Last month, Louis Klarevas wrote in TNR about what President Obama could have done to stop the execution.) “Texas is not bound by a foreign court’s ruling,” Perry spokeswoman Katherine Cesinger said when questioned about the matter. “If you commit the most heinous of crimes in Texas, you can expect to face the ultimate penalty under our laws.”

Napoleon Beazley. In 1994, Napoleon Beazley shot John Luttig during an attempted carjacking. At the time, Beazley was only 17 years old, and he was president of his senior class. John Luttig’s son, Michael Luttig, went on to become a U.S. District Judge. When the case reached the U.S. Supreme Court, three justices—Antonin Scalia, Clarence Thomas, and David Souter—had to recuse themselves because they had relationships with Michael. The remaining six justices voted 3-3 on Beazley’s appeal, with the tie resulting in a rejection. Beazley was executed in 2002. The Supreme Court later banned executions for offenders under 18 in 2005.

Frances Newton. In 2005*, after 18 years on death row, Frances Newton was the first African American woman to be executed in Texas since the death penalty was reintroduced in 1976. She had been convicted for the murder of her husband and two children, but there was no physical evidence to prove that Newton had committed the crime. In addition to the lack of physical evidence used to convict Newton, she had limited access to an adequate defense attorney. Her trial lawyer, Ronald Mock, was infamously incompetent and later suspended by the Texas State Bar. Newton maintained her innocence throughout the entire trial.

Milton Mathis. Despite evidence of mental retardation, Milton Mathis was executed in 2011* for the murder of two people. Intelligence tests administered to Mathis scored him in the low 60s, indicating significant mental disability. The prosecutors claimed, despite these scores, that Mathis was “street-smart” and that his behavior indicated he had a “normal” level of intelligence. Perry claims that he did not have the ability to offer a reprieve for Mathis without recommendation from the Texas Board of Pardons and Paroles. In 2001, Perry vetoed a bill that banned the execution of the mentally disabled.