(CNN) -- With his opinion for a narrow majority of the Supreme Court, upholding major provisions of the Affordable Care Act, Chief Justice John G. Roberts Jr. has, for the first time since his confirmation as chief justice in 2005, breached the gap between the conservative and liberal wings of the court on a polarizing political issue. News: Legal scholars unsurprised by Roberts In doing so, he has jettisoned his reputation as a predictable conservative vote on controversial issues, such as campaign finance reform and affirmative action, that have been decided by a divided court. Roberts, in finding the critical provisions of the Affordable Care Act constitutional, has followed the example of his predecessor, Chief Justice Charles Evan Hughes, who led the court during the tumultuous constitutional battles over President Franklin D. Roosevelt's New Deal legislation. Hughes, like Roberts, sometimes found narrow grounds to uphold New Deal legislation and, as a result, cautiously steered the court away from the public perception that justices voted according to their political values, not constitutional principle.
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James Simon: Chief justice breached gap between court's conservative, liberal wings
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He says Roberts upended reputation as predictable conservative, like a predecessor
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He says FDR-era Chief Justice Charles Evans Hughes also kept politics out of decisions
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Simon: Roberts left fate of law with political branches and voters, where it belongs
@placeholder skillfully worked to promote the court's public image as nonpartisan, not just in his narrow opinions, but, dramatically, in defending the justices against FDR's attacks and his court-packing plan.
News: Emotions high after @placeholder upholds health care law