How is a defendant's sentencing under the Eighth Amendment proportionality?

Defendant cites the objective criteria proposed in Solem v. Helm (1983) 463 U.S. 277, 292, as a guide to determining proportionality under the Eighth Amendment: "(i) the gravity of the 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." However, defendant provides no analysis of such factors in relation to the crimes he committed, and relies solely upon his analysis under the California Constitution. We thus turn first to that discussion.