Gregg v. Georgia (1976)
Tony Gregg had been sentenced to death in Georgia for armed robbery and murder.  When he appealed his sentence as "cruel and unusual" and a violation of the Eighth Amendment, the US Supreme Court in a 7-2 decision upheld the sentence.  The court ruled that the death penalty was an appropriate punishment in extreme criminal cases and that Georgia had developed appropriate standards and other safeguards to guide a jury's deliberations in capital cases.  

http://www.oyez.org/cases/1970-1979/1975/1975_74_6257/