What is required by the Eighth Amendment to prohibit the use of the death penalty?

The Eighth Amendment to the United States Constitution prohibits "cruel and unusual punishment" and "contains a 'narrow proportionality principle' that 'applies to noncapital sentences.' [Citation.]" (Ewing v. California (2003) 538 U.S. 11, 20 [155 L.Ed.2d 108] (Ewing).) What is required is not " 'strict proportionality between crime and sentence. Rather, [the Eighth Amendment] forbids only extreme sentences that are "grossly disproportionate" to the crime.' [Citation.]" (Id. at p. 23.)

Relying on Coker v. Georgia (1977) 433 U.S. 584 [53 L.Ed.2d 982], defendant argues her sentence of life with the possibility of parole plus nine years four months is "an absurdity that serves no legitimate penal purpose." However, Coker held the death penalty is "grossly disproportionate and excessive punishment for the crime of rape and is therefore forbidden by the Eighth Amendment as cruel and unusual punishment." (Id. at p. 592.) Thus, Coker is so factually dissimilar as to offer defendant no assistance whatsoever.