What position other than president does lincoln claim that gives him the power to issue the emancipation proclamation

Though he had always hated slavery, President Lincoln did not believe the Constitution gave him the authority to bring it to an end—until it became necessary to ... Lincoln used his authority as Commander in Chief under the U.S. Constitution to issue the Emancipation Proclamation, which took effect on January 1, 1863.

Bis correct you

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