Here are three of the most prominent judges on the 9th Circuit, reflecting the broad span of its members' ideological perspectives.
Chief Judge Alex Kozinski
* Appointed by President Reagan in 1985 at the age of 35.
* Chief judge since 2007 and as such sits on all 11-judge en banc rehearings, giving an advantage to the conservative faction, with whom he tends to vote on most issues.
* Praised by the left and the right for his razor-sharp intellect and eloquent opinions. The Romanian-born jurist's libertarian views give him a quirky side that last year immersed him in scandal for sharing sexually explicit jokes and pictures over the Internet.
* Credited with instigating the court's habit of writing dissents from decisions to deny en banc rehearings, to call Supreme Court attention to cases seen as straying from the more conservative line toed by circuit judges elsewhere.
Circuit Judge Stephen Reinhardt
* Appointed by President Carter in 1980.
* Among the court's most liberal members; married to Ramona Ripston, head of the American Civil Liberties Union of Southern California.
* Sits on a special judicial panel weighing the risks to inmates' rights from the massive overcrowding in California prisons.
* Expresses zero tolerance for procedural errors in death penalty cases, having sat on 18 since his appointment and never voted in support of an execution.
"You don't have to think someone is innocent to say his trial wasn't fair or constitutional," he says.
Circuit Judge Diarmuid F. O'Scannlain
* Appointed by President Reagan in 1986.
* The most consistent voice on the right, O'Scannlain often finds himself in the company of the conservative judges named to the court over the last 15 years.
* Strict in applying immigration laws that give lower-court judges the power to decide the facts of a case, including whether "unusual or extraordinary hardship" would result from an immigrant's deportation.
* Concedes that the court's decisions can vary sharply depending on which three of its 48 judges are hearing a case.
"That's the 800-pound gorilla in the room," he says of the inconsistent rulings that he and others try to correct with calls for en banc rehearings.