PHOENIX - The Arizona Department of Corrections director is resigning in September.

In an email sent to all his staff Friday, Charles Ryan said he will be stepping down effective Sept. 13.

Gov. Doug Ducey released a statement about Ryan's resignation Friday:

"Director Ryan has committed his life to serving in the corrections field for more than 40 years. His dedication to ensuring public safety and providing inmates a real second chance, has made him a nationally-recognized leader." 

In his resignation letter, Ryan counted among his proudest achievements the elimination of maximum custody for women and juvenile inmates and improved mental health services.

But some corrections officer union members begged to differ about Ryan's legacy. He's had a troubled history at the head of Arizona’s prisons since he was named corrections director in 2009. And the state has faced growing pressure from civil rights advocates calling for Ryan to be fired over alleged inhumane conditions in prisons.

The most recent controversy involved the Lewis prison in Buckeye, where close-custody inmates had tampered with their cell doors so they could be opened from the inside. A video released by the Arizona Corrections Peace Officer Association shows several inmates attacking officers.

The AZCPOA alleged poorly kept facilities put corrections officers and prisoners at risk.

Gov. Doug Ducey responded by placing former Arizona Supreme Court Justices Rebecca Berch and Ruth McGregor in charge of an investigation into prison security.

But that wasn’t the first high-profile controversy Director Ryan has dealt with during his tenure. In 2014, he came under fire when the execution of double-murderer Joseph Wood drew national attention—with critics claiming it was botched. A review found Ryan did nothing wrong, but the execution brought about a five-year hiatus on the death penalty in Arizona.

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The next year, an inmate riot at a private prison in Kingman exposed a lack of supervision at the facility. The prison operator was fired, and Ryan accepted no blame for the gap in oversight.

In 2018, Ryan was found in civil contempt of court and fined $1.4 million for failing to adequately improve health care for inmates.

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Ryan said Friday that he would “pursue new opportunities” spend more time with his family during his retirement.