the granting of an amnesty or a collective pardon;
http://www.cdep.ro/pls/dic/cd.show?cpage=atworkg_2

In case where collective pardon is
granted, the death ... 55 condemned inmates, all male,
waiting for the Royal Pardon ... and Murder, 28. 7. Offense against Narcotic law, ...
www.correct.go.th/death.htm - 5k

The major explanation seems to be competition from non-individual sentence reduction measures which have been common in France since 1980. In that year President Giscard D’Estaing responding to a steep rise in the prison population granted a collective pardon. That has now become standard practice.

being necessary, except the law on the state budget and the law ... the conditions of
their execution;; the granting of an amnesty or a collective pardon ...


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Note added at 2002-10-05 08:58:18 (GMT)
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Main Entry: am·nes·ty
Pronunciation: \'am-n&-stE
Function: noun
Inflected Form(s): plural -ties
Etymology: Greek amnEstia forgetfulness, from amnEstos forgotten, from a- + mnasthai to remember -- more at MIND
Date: 1580
: the act of an authority (as a government) by which pardon is granted to a large group of individuals
- amnesty transitive verb

go for *amnesty* = which means collective pardon, in fact.
merriam webster\'s
http://www.m-w.com/cgi-bin/dictionary