It is unlikely that Democrats will be able to block Brett Kavanaugh, President Trump’s nominee to replace Anthony Kennedy, from taking a seat on the Supreme Court. But they can do all they can to clarify the stakes in this battle, to illustrate in advance of the midterm elections what Republican control of the White House and Congress really means for the country over the long term.

Here’s one important area in which they can do that: They must press Kavanaugh to clarify his thinking on the question of whether presidents are above the law, or more specifically, how much power presidents have with regard to investigations into themselves.

Many observers are pointing to a 2009 law review article by Kavanaugh that argues that “we should not burden a sitting president with civil suits, criminal investigations or criminal prosecutions,” and instead that “impeachment” is the proper “mechanism” against a “bad-behaving or law-breaking president.” He suggests that “Congress might consider a law” exempting presidents in office “from criminal prosecution and investigation, including from questioning by criminal prosecutors.”

This has obvious implications for special counsel Robert Mueller’s probe involving Trump and his associates, but the reporting on it has been a bit off. Kavanaugh is not saying he believes presidents are currently constitutionally protected from investigations and lawsuits, i.e., that presidents are not legitimate targets or subjects of such actions. Rather, he is saying that this perhaps should be the case and that Congress should pass a law making it so.

But this distinction actually sets up a good line of questioning for Senate Democrats to pursue at Kavanaugh’s confirmation hearing. They can ask him to clarify his thinking on the constitutionality of these matters.

CLARIFYING HIS THINKING

“I would ask, ‘With regard to this language, were you suggesting that there are constitutional problems with an independent prosecutor investigating a president? Or were you merely suggesting you don’t think this is wise?’ ” Stephen Vladeck, a law professor at the University of Texas at Austin, told me Tuesday.

This question, of course, is germane because the president’s own lawyers have asserted that Trump can “terminate” Mueller’s investigation, or pardon any of his associates being investigated by Mueller, at will, and that this would not constitute obstruction of justice because Trump is the nation’s “chief law enforcement officer.”

Senators probably could not get Kavanaugh to answer specific questions about Trump and the Mueller probe. But Vladeck notes they can use his previous writings to pivot to more general questions along these lines.

“A senator could ask, ‘Do you believe a president has the Article II authority to shut down a special counsel investigation into himself, or pardon anyone, including himself, for any reason?’ ” Vladeck says. “If he dodges, the question could then be, ‘Given that you’ve previously written about the relationship between presidents and these kinds of investigations, isn’t this a fair question?’ ”

Kavanaugh might dodge again. But Vladeck adds: “There’s still value to having these questions asked on the public record, and there could be non-answers that are very loud.”

Sen. Richard Blumenthal, D-Conn., a member of the Judiciary Committee, told me Tuesday that Democrats should pursue such questions. That’s because there are, in fact, scenarios like this involving Trump and Mueller that could come before the Supreme Court – if Trump refuses a sitdown interview with Mueller, and defies a subpoena, or if he tries to end the Mueller inquiry without good cause, among other things.

A SWING VOTE ON TRUMP’S AUTHORITY

Kavanaugh “would very likely be the decisive swing vote” on whether Trump “can pardon himself or others, whether he has to comply with a subpoena to appear before a grand jury, whether he can be indicted as a president,” Blumenthal said.

He added that Kavanaugh should be asked: “Are there any limits to the president’s pardon power when it may affect an investigation involving the president as a potential target?” Blumenthal stressed that Kavanaugh should be pressed on whether he will recuse himself from any such matters.

The big issue here, as the American Constitution Society’s Caroline Fredrickson and ethics attorney Norm Eisen point out, is that Kavanaugh’s skepticism of investigations into sitting presidents was likely part of his “appeal” to Trump, and suggests Kavanaugh may believe presidents enjoy a level of power over investigations into themselves that may mean he won’t “serve as a check on his abuses of power.” Blumenthal told me that Kavanaugh should be asked flat-out: “Do you believe the president is above the law?”

That may seem like an overly open-ended question, and it’s one that White House advisers have answered in the negative. But it really is a core issue that needs to be explored. As Sean Illing of Vox has explained, Trump’s lawyers have adopted a series of legal theories (the president cannot obstruct justice by definition; his pardon powers are limitless) that actually do raise difficult questions about whether the law applies to the president. More to the point, before long, events may force these questions upon us, requiring answers to them. Democrats must do all they can to flesh out a detailed picture of what Kavanaugh really thinks in that regard.