A 46-year-old inmate at the nation’s highest-security prison was convicted Tuesday in Denver’s federal court in the 2013 attack of two librarians and a case manager as they delivered books to his cell.
Ishmael Petty was found guilty of three counts each of assault, resisting and impeding a federal employee after a two-day trial. He is scheduled to be sentenced Oct. 30.
On Sept. 11, 2013, Petty attacked the three Federal Bureau of Prisons employees at the Administrative Maximum Security Prison — known as the ADX or Supermax — in Florence.
“At ADX there is an outer door, a secure area and then an inner door before entering the actual cell,” Colorado’s U.S. attorney’s office said Tuesday.
“While the … employees believed that Petty was in his cell, he was in fact hiding in the area between the outer and inner doors.”
Petty was wearing self-made body armor formed from “cardboard box-like material” and was wielding a shank, prosecutors say.
“When the attack began, Petty threw hot sauce in the eyes of one BOP librarian and then attacked the other librarian,” the office said.
“The third BOP employee, a case manager, quickly came to their aid and called for help.”
Federal prosecutors say Petty took control of two of the employees’ batons and used them in his attack.
When a call for help was made, Petty returned to his cell, officials say.
Petty is serving a life sentence at ADX for killing his 71-year-old cellmate at a federal prison in Louisiana.
He was being held at the Louisiana prison on a 420-month sentence for an armed bank robbery in Mississippi where he was wearing a police officer’s uniform, federal prosecutors say.
Petty faces up to 20 years and up to a $250,000 fine for each count he was convicted of in the 2013 attack.
The ADX in Florence is home to the nation’s most notorious criminals.
Jesse Paul: 303-954-1733, jpaul@denverpost.com or twitter.com/JesseAPaul