Thurgood Marshall, Furman v. Georgia — Concurring Opinion…
“ There is no more complex problem than determining the deterrent efficacy of the death penalty. "Capital punishment has obviously failed as a deterrent when a murder is committed. We can number its failures. But we cannot number its successes. No one can ever know how many people have refrained from murder because of the fear of being hanged." 93 This is the nub of the problem and it is exacerbated by the paucity of useful data. The United States is more fortunate than most countries, however, in that it has what are generally considered to be the world's most reliable statistics. ”
