Is a life sentence without the possibility of parole unconstitutional?

In arguing there is a violation of the Eighth Amendment proscription against "cruel and unusual punishments," defendant relies upon Solem v. Helm (1983) 463 U.S. 277, 103 S.Ct. 3001, 77 L.Ed.2d 637, in which the court found a life sentence without the possibility of parole for a seventh nonviolent felony was unconstitutional. In Solem, a bare majority of the court held "a court's proportionality analysis under the Eighth Amendment should be guided by objective criteria, including (i) the gravity of the [39 Cal.App.4th 1135] offense and the harshness of the penalty; (ii) the sentences imposed on other criminals in the same jurisdiction; and (iii) the sentences imposed for commission of the same crime in other jurisdictions." (Id. at p. 292, 103 S.Ct. at p. 3010, 77 L.Ed.2d at p. 650.)