WASHINGTON — Chief Justice John Roberts defended his colleagues Saturday as "jurists of exceptional integrity and experience" and said it was a misconception that Supreme Court justices do not follow the same set of ethical principles as other judges.

In his year-end report on the federal judiciary, Roberts for the first time addressed a growing controversy about when justices should recuse themselves from cases and whether a code of conduct that covers lower-court judges also should apply to the justices.

The recusal issue has been most prominent as the court prepares to address the constitutionality of the health-care law.

Groups on the right have demanded that Justice Elena Kagan withdraw from the court's consideration of the case because of her work for President Obama as solicitor general. Liberal groups have called on Justice Clarence Thomas to recuse himself because of the conservative political activities of his wife, Virginia Thomas. There is every indication that both justices intend to participate in the health-care case.

"I have complete confidence in the capability of my colleagues to determine when recusal is warranted," Roberts wrote. "They are jurists of exceptional integrity and experience whose character and fitness have been examined through a rigorous appointment and confirmation process."

He did not mention any justices by name.

Federal law requires that judges disqualify themselves when they have a financial interest in a case, have given advice or expressed an opinion "concerning the merits of the particular case" or when their "impartiality might reasonably be questioned." For lower-court judges, such a decision can be reviewed by a higher court, but the Supreme Court has no such review.

Roberts said the Supreme Court's unique status made it impossible for the justices to follow the practices of lower-court judges in recusal matters. Lower-court judges can be replaced if they decide to disqualify themselves, he said, and their decisions about recusal can be reviewed by higher courts.

"The Supreme Court does not sit in judgment of one of its own members' decision whether to recuse in the course of deciding a case," he wrote. "Indeed, if the Supreme Court reviewed those decisions, it would create an undesirable situation in which the court could affect the outcome of a case by selecting who among its members may participate."

The Supreme Court is expected to decide the fate of the 2010 health-care law by the end of June, just as the 2012 presidential campaign enters its crucial final months.

Roberts also addressed critics who say Supreme Court justices should be bound by the same code of judicial ethics that applies to other federal judges.

He pointed out that the justices voluntarily follow the same rules, but said they should not be bound by them.

Justices consult the Judicial Conference's Code of Conduct as a "starting point," but it cannot answer all questions, he said.

Justices may also "turn to judicial opinions, treatises, scholarly articles and disciplinary decisions" and seek advice from experts and colleagues.

Material from The New York Times is included in this report.