Re: Probable Cause
An officer generally needs no specific, articulable cause to run a check on someone ... so long as it is for a lawful purpose (as opposed to seeking a date, for instance).
I cannot say whether your local courts will see that the name of a registered owner or a co-resident and a general description is sufficient to justify a detention. This can vary by state and jurisdiction, and will depend on the details provided by the officer. If it is worth the expense of an attorney and a court challenge, give it a go.
A Nor Cal Police Sergeant
"Make mine a double mocha ...
... and a croissant!"
Walk humbly with your God
-- Courageous, by Casting Crowns