I'll just hazard a guess, based upon my experience.
Old old Court records, maybe other records, etc often contain a first and last, but no middle name; older records weren't available electronically.
During my background check they came up with people in States I've never even been to, and about 8 more people in the area surrounding Houston, with my first and last names (of all ages). (And I don't have a real common name, I didn't think) One clerk in a County/State I had never been to wanted $1,000 to do a manual search of paper records and send copies .... I got my license in the mail just prior to having to pay that; the DPS figured it out or got verification from them without me needing to.
They had to verify none of those people were me' against what I sent showing from clerks that I had no criminal record anywhere.
I mean, the police gave me and a buddy a ride to the police station in the early 1960s for hunting frogs outside the city with BB guns and called our parents, so his mom didn't get to cook frog legs that night,
but it wasn't an "Unauthorized Carrying a Weapon" charge, our mommas picked us up at the station and told us to use bow and arrows the next day instead of BB guns, so the police wouldn't think they were real guns.
(The next day, we used bows and arrows and my buddy's mom made turtle soup AND frog legs; we went to the bayou instead of the field ... less visible from the road)
But, the background check is thorough enough that they needed to know we weren't criminals; just hungry. And, that the other people they found named with my first and last names weren't me.
