The US Supreme Court on Monday announced its first formal code of conduct governing the ethical behaviour of its nine justices, bowing to months of outside pressure over revelations of undisclosed luxury trips and rubbing shoulders with wealthy benefactors.

The new code drew mixed reviews, with some critics noting the apparent absence of any enforcement mechanism. It was adopted after a series of media reports detailing ethics questions surrounding some Supreme Court members, in particular conservative Justice Clarence Thomas, even as Senate Democrats pursued long-shot legislation to mandate an ethics code for the nation's top judicial body.

The nine-page code contains sections codifying that justices should not let outside relationships influence their official conduct or judgment, spelling out restrictions on their participation in fundraising and reiterating limits on the accepting of gifts. It also states that justices should not "to any substantial degree" use judicial resources or staff for non-official activities.

A commentary released with the code elaborating on some of its provisions said that justices who are weighing a speaking engagement should "consider whether doing so would create an appearance of impropriety in the minds of reasonable members of the public."

Unlike other members of the federal judiciary, the Supreme Court's life-tenured justices had long acted with no binding ethics code. That absence, the court said in a statement accompanying the code, had led some to believe that the justices "regard themselves as unrestricted by any ethics rules."

"To dispel this misunderstanding, we are issuing this code, which largely represents a codification of principles that we have long regarded as governing our conduct," the statement said.

The court has been buffeted for months by revelations regarding justices over undisclosed trips on private jets, luxury vacations, real estate and recreational vehicle deals, and more.

Senator Dick Durbin, who chairs the Democratic-led Senate Judiciary Committee, called the code a "step in the right direction." But Durbin held open the possibility of further legislative efforts if he determines the code falls short of "the ethical standards which other federal judges are held to." (Reuters)