Peter Zack Geer (August 24, 1928 – January 5, 1997) was an American lawyer and a Democratic politician from the U.S. state of Georgia. Geer was born in Colquitt in Miller County in southwestern Georgia. In 1951 he graduated from the Walter F. George School of Law at Mercer University in Macon and became a prominent attorney. After service as a member of the Georgia House of Representatives, Geer was the fifth Lieutenant Governor of Georgia from 1963 to 1967 under his fellow Democrat, Governor Carl Sanders. To win the lieutenant governorship, Geer defeated in the 1962 primary runoff his fellow segregationist and later Governor Lester Maddox, a restaurateur from Atlanta, by a margin of 55 to 45 percent.