Important for :
To free someone from all blames :
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Kindly refer to the video to get to know the context the word is generally used in.

Exonerate (Verb) :

1. (of an official body) absolve (someone) from blame for a fault or wrongdoing.

Ex. "an inquiry exonerated those involved"
Ex. It's another matter that in the equally sensational TANSI land-deal case, the Supreme Court finally exonerated Jayalalithaa of any wrong-doing.
Synonyms: absolve, clear, acquit, declare innocent, find innocent, pronounce not guilty, discharge.

2. release someone from (a duty or obligation).

Ex. "Pope Clement V exonerated the king from his oath to the barons"

Synonyms: release, discharge, relieve, free, liberate.