and I cannot find an exact answer to your question .. I offer this though.
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http://www.law.uoregon.edu/org/olr/archives/81/81_Or_L_Rev_231.pdfDefining Clemency Executive clemency is an enigma. Its definition is simple enough: it “characterizes a judgment or action
a person with the power to exact punishment declines to exact all or some of what he or she is entitled to exact.” Put differently, clemency refers to the power of an executive to alter the outcome of a judicial decision by diminishing the impact of a defendant’s punishment--to change the specifics of a court’s judgment by remitting a criminal’s sentence or simply pardoning her or his offense. The Supreme Court has defined clemency as “an act of grace, proceeding from the power intrusted with the execution of the laws, which exempts the individual, on whom it is bestowed, from the punishment the law inflicts for a crime he has committed.” In the context of capital punishment, clemency often manifests itself in the grant of relief by a governor to a death row inmate. In such instances the capital sentence is most often replaced by a sentence of life imprisonment. The key to understanding clemency is to view it in terms of a reduction or suspension of the particulars of punishment. Typically synonymous with concepts such as “mercy, leniency, kindness, and forgiveness,” executive clemency can take multiple forms and can be administered in a variety of different ways. *236 Radelet and Zsembik identify three major types of executive clemency: “pardons (which invalidate both the guilt and the punishment of the defendant), reprieves (which temporarily postpone the execution), and commutations (which reduce the severity of the punishment).” The most common, but certainly not exclusive, use of all three styles can be found in the arena of capital punishment. Indeed, governors (and now presidents) are regularly asked either to pardon death row inmates, or at a minimum commute their individual sentences. A comparison across states can also be helpful in augmenting our understanding of clemency.
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The article is very long but may be of some help.
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