Here is the full list of all 12 Verbal Verdict achievements.
Crack your first case successfully
Crack all cases in the game
Get an S grade for the Sophia Bennet case
Use the full time limit of a case
Complete the case with more than 50% of time remaining
Complete the case correctly within 20 seconds
Enable Noir Mode, Play an entire case in Noir mode
Get an S grade for the Party case
Get an S grade for the Mr. Turner case
Get an S grade for the Cabby case
Get an S grade for the Vanished Manuscript case
Get an S grade for the Walter case