free pardon 
noun British
An unconditional remission of the legal consequences of an offence or conviction: he was given a free pardon...
- There are free pardons, there are conditional pardons, there is the remission of sentence, there are a range of options.
- He was also aware that a £350 reward had been offered and possibly a free pardon to any one giving evidence leading to the conviction of the murderers of William Lilley.
- The Home Secretary argued that free pardons were granted only when the moral and technical innocence of the convicted person could be clearly established.