=The Pardoning Power of the President.=--The Constitution authorizes the President "to grant reprieves and pardons for offenses against the United States except in cases of impeachment."[85] The President cannot, of course, pardon offenses against state law. Offenses against the postal laws, the revenue laws, the laws against counterfeiting, and the national banking laws are those for which pardons are most frequently sought. Crimes committed in the territories are, however, offenses against the laws of the United States, and are frequently the object of applications for pardon. [85] Impeachment offenses were excepted for the purpose of preventing the President from granting pardons to his own appointees and thereby shielding them from the consequences of their acts. For definition of pardon and reprieve, and further discussion of the nature and purpose of the pardoning power, see p. 102-103. With the exception of the limitation in regard to impeachment offenses, the President's power of pardon is absolute. His power is not restricted by a board of pardons as is that of the governors of some of the states, nor can Congress in any way abridge his power or restrict the effect of a pardon granted by him. Moreover, he may grant a pardon before as well as after conviction, though this is rarely done in the case of individual offenses. It is sometimes done, however, where large numbers of persons have become liable to criminal prosecution for participation in rebellion, resistance to the laws, and similar acts. _Amnesty._--In such cases the pardon is known as an "amnesty," and is granted by proclamation. Thus in December, 1863, President Lincoln issued an amnesty proclamation offering a full pardon to all persons in arms against the United States provided they would lay down their arms and return to their allegiance. In April, 1865, President Johnson issued a proclamation offering amnesty to all those who had borne arms against the United States, with certain exceptions and subject to certain conditions. The last instance of the kind was the proclamation issued by President Harrison, in 1893, granting amnesty to those Mormons who had violated the anti-polygamy laws of the United States. _Commutation._--The power to pardon is held also to include the power to commute a sentence from a heavier to a lighter penalty, and also to reduce a fine or remit it entirely. _Parole._--In 1910, Congress passed a law providing for the release on parole of federal prisoners sentenced to a term of more than one year, except life prisoners, provided their conduct has been satisfactory. At each of the three federal prisons there is a board of parole charged with hearing applications for release.