Elizabeth Holtzman is a former US representative from New York. She won national attention for her role on the House Judiciary Committee during Watergate and was subsequently elected district attorney of Kings County, New York (Brooklyn). She is a Harvard Law School graduate and co-author with Cynthia L. Cooper of "The Impeachment of George W. Bush: A Practical Guide for Concerned Citizens." The opinions expressed in this commentary are solely those of the author. View more opinion articles on CNN.

(CNN) President Donald Trump's Supreme Court nominee Brett Kavanaugh declared in 2016 that he wanted to "put the final nail" in the coffin of Morrison v. Olson, a Supreme Court decision that upheld a court-appointed special prosecutor's power to investigate high-level executive branch criminality. Recently CNN also unearthed a 1998 video of Kavanaugh saying, "It makes no sense at all to have an independent counsel looking at the conduct of the President." ("Special prosecutor" and "independent counsel" can be used more or less interchangeably, although there are slight differences.)

As co-author of the 1978 special prosecutor statute, I find these views troubling. They don't bode well for Robert Mueller's investigation.

Elizabeth Holtzman

The nail-in-the-coffin remark generated significant media attention, but what does it really mean? A closer look at the 1988 Morrison decision -- particularly at the dissent Kavanaugh appears to be echoing -- shows why Kavanaugh's statement is so worrisome. If he is confirmed and uses a long enough nail, overturning Morrison could lead to ending the Mueller probe, too.

Many legal thinkers on the right have never accepted the Morrison decision, looking instead to Justice Antonin Scalia's dissent in the case, which claimed the special prosecutor provisions were unconstitutional. But Scalia's opinion was riddled with errors. He argued that prosecutors who investigate presidential criminality should give the president and top aides and officials "sympathetic" treatment. You read that right: Scalia actually wrote that presidents deserve a prosecutorial "forum that is attuned to the interests and policies of the Presidency." It's supposed to be a "natural advantage" that presidents earn by winning elections, according to Scalia.

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Aside from sounding crazy on its face, that dissenting opinion is deeply hostile to the fundamental point of the special prosecutor statute: No one, not even the president, is above the law. Therefore no one, not even the president, should get preferential treatment from "sympathetic" prosecutors and be insulated from prosecutors who are objective and follow wherever the evidence leads.

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