What he did was betray his oath to be faithful to the Constitution of the United States.
Who he betrayed were the hundreds of millions of Americans -- past, present and future -- whole generations in the past who have fought and died for a freedom that he has put in jeopardy, in a moment of intellectual inspiration and moral forgetfulness, 300 million Americans today whose lives are to be regimented by Washington bureaucrats, and generations yet unborn who may never know the individual freedoms that their ancestors took for granted.
Some claim that Chief Justice Roberts did what he did to save the Supreme Court as an institution from the wrath -- and retaliation -- of those in Congress who have been railing against Justices who invalidate the laws they have passed. Many in the media and in academia have joined the shrill chorus of those who claim that the Supreme Court does not show proper "deference" to the legislative branch of government.
But what does the Bill of Rights seek to protect the ordinary citizen from? The government! To defer to those who expand government power beyond its constitutional limits is to betray those whose freedom depends on the Bill of Rights.
Similar reasoning was used back in the 1970s to justify the Federal Reserve's inflationary policies. Otherwise, it was said, Congress would destroy the Fed's independence, as it can also change the courts' jurisdiction. But is it better for an institution to undermine its own independence, and freedom along with it, while forfeiting the trust of the people in the process?