My problem is the grammar correcter is telling me to use "had proven" while this grammar web site says 'proven' is typically used as an adjective and 'proved' a verb. So is my grammar program just not bilingual? And should I go with the verb/adjective distinction or my word processor's grammar preference? Just wondering about consensus of opinion.
"Proven" is the preferred past participle of "prove", and so it is the principal verb in many compound tenses. "Proved" is the simple past tense, but is also permissible as a past participle. However, "proven" is not a proper simple past tense.
Either one is right. I think "proven" is favored in Scotland. I thought I read that a Scottish jury had its choice of three verdicts in a criminal trial: Guilty, Innocent, and Not Proven (the implication being that he probably did it, but the evidence doesn't support a guilty verdict).