There are four (4) main reasons to ONLY use a vendor who
supplies Freshly Retrieved Data. (Your other alternative
is to use stored data from large accumulated databases.)
You don't want to violate Federal law. See the FTC
staff opinion letter about STORED DATA.
Stored data vendors purchase update tapes or CDROMS
at best every 3 months -- usually every 6 months or
much longer, and you can NOT afford to wonder if your
candidate has been arrested and convicted since your
vendor's database was long ago updated.
Database vendors are the same organizations who
bring you the inaccuracies of your credit, driving,
and other reports.
You can't afford to get into an employee lawsuit and
have as your defense, questionable documents produced
by vendors well known to be fined by the FTC for prior
background checking violations and errors.