From the NYT -
The U.S. Chamber of Commerce, which has helped lead opposition to the health care law, has been hosting moot court sessions to prepare lawyers involved in the case. Advocates on all sides of the issues, including Tea Party leaders who are against the law and health care professionals who favor it, are planning rallies. Many groups, like the American Constitution Society, liberal backers of the law and of Congress’s power to regulate commerce, are setting up war rooms and daily briefings on the Supreme Court steps...
...But does the cajoling from outside groups have any real impact on the court’s decisions? At least in the case of the formal amicus briefs filed with the court, research suggests that the answer, increasingly, is yes.
A study published last year in The National Law Journal by Mr. Franze and R. Reeves Anderson, his colleague at the law firm Arnold & Porter, found the Supreme Court justices not only receiving more amicus briefs than ever before, but also citing them as support for their opinions far more often as well.