[anigbrowl]

Sure, you can use a photocopier as a lie detector if your subject is sufficiently gullible. The real questions are why you think it's needed and what level of abuse/misapplication you're willing to be responsible for.

If your use cases cases as described in the OP are for real rather than satirical, you are a naive person and should spend more time reading about the history of technology to understand how and why good intentions can have catastrophic outcomes.