The first, simple judicial procedure would only need to declare him ineligible, disallowing his installation and inauguration, assuming he were elected. It would still be very appropriate to have done even if he weren't elected, for the good of the Republic and to set its record straight.
Secondary procedures, assigning blame and penalty would almost certainly let everyone other than the candidate himself, inasmuch as he's declared to Brokenjaw that his records have been kept private. But, if Kerry chose to get into finger pointing, we could really see the Dems go down the drain for the next century.
HF