The word for today is…
exculpatory (adj) – Tending to clear someone, especially a suspect, of guilt or blame; exonerative.
Source : The Free Dictionary
Etymology : 1779, from exculpate + -ory.
exculpate – “To clear from suspicion of wrong or guilt,” 1650s, from Medieval Latin exculpatus, past participle of exculpare, from Latin ex culpa, from ex “out of” + culpa ablative of culpa “blame, fault.”