Chief Justice John Roberts said Saturday that he has "complete confidence" in his colleagues' ability to step away from cases where their personal interests are at stake, and noted that judges should not be swayed by "partisan demands."

The comment, included in Roberts' year-end report, comes after lawmakers demanded that two Justices recuse themselves from the high court's review of President Barack Obama's health care law aimed at extending coverage to more than 30 million people. Republicans want Justice Elena Kagan off the case because of her work in the Obama administration as solicitor general, whereas Democrats say Justice Clarence Thomas should back away because of his wife's work with groups that opposed changes to the law.

While not mentioning the upcoming health care ruling, or any case in particular, Roberts' year-end report dismissed suggestions that Supreme Court Justices are subject to more lax ethical standards than lower federal courts and said each Justice is "deeply committed" to preserving the Court's role as "an impartial tribunal" governed by law.

"I have complete confidence in the capability of my colleagues to determine when recusal is warranted," wrote Roberts. "They are jurists of exceptional integrity and experience whose character and fitness have been examined through a rigorous appointment and confirmation process. I know that they each give careful consideration to any recusal questions that arise in the course of their judicial duties."