It doesn't seem that implausible given a military (or terrorist) operation of some kind. If you're raiding an important locked-down government facility, armed t

It doesn't seem that implausible given a military (or terrorist) operation of some kind. If you're raiding an important locked-down government facility, armed to the teeth but unable to enter the facility with explosives, then it seems reasonable to try forcing an employee to stand next to the scanner (which this technology obviously wouldn't prevent), or knocking them out or killing them and putting their face up to the scanner. Though ideally the facility would use MFA (combining the retina scan with a passcode or something).