The Department of Corrections said plans were under way last summer for the technology. The process was sped up after an inmate escaped by posing as another inmate who was up for parole. He was later captured in New York.This really happens.
Iris biometrics are highly suited to this particular application because even though each transaction is slower, they are more difficult to fake than fingerprint biometrics.
The trade-off in speed isn't really a deal-breaker in a prison environment.