Common way to say "give it some veracity"

I want a common idiom or expression that says "to give (something) veracity"

I was thinking "give it some salt", but that seems like its not a common expression.

Solution 1:

How about substantiate? Or some synonyms for substantiate from the Oxford American Writer's Thesaurus:

prove, show to be true, give substance to, support, uphold, bear out, justify, vindicate, validate, corroborate, verify, authenticate, confirm, endorse, give credence to.

Solution 2:

You could try lend credence to:

Her torn clothing and scratches on her arms and shoulders lent credence to her claim of having been attacked.

Solution 3:

How about back it up, as in We have the numbers to back that up or That claim sounds awfully flimsy; you need to back it up.

Solution 4:

Prove it. (must put thirty characters)