What criminal background checks disqualify a nurse?
It's not the check that disqualifies, but the underlying action.
For example; if patients mysteriously died while in your care, that
is not the fault of the background check.
I would say that that which would disqualify a nurse is the same as would disqualify anyone except that nurses have the opportunity to do more harm than say, a burger flipper.
If I were hiring a nurse, I would be very concerned about drug use and abuse.
Actually, most local laws forbid convicted felons from registering to be a nurse. You can complete the schooling. But not work in health care. However, laws vary from state to state, county to county, and town to town.