Over the decades since Justice Stevens’ confirmation, hearings for Supreme Court nominees have become unforgiving of candor (while simultaneously purporting to crave it) and brutally punishing of nominees with a habit of expressing strong views.

Elena Kagan is the perfect nominee for this process. Since she has not been a judge, she has no opinions to scrutinize. And, apparently eager to become a justice since her high school years, she has been scrupulously careful in her public writings and speeches, and has avoided making ideological enemies.

Despite a dearth of material, and even though there is no evidence that Kagan will shift the Court’s ideological center of gravity to any meaningful degree, Senate Republicans are resolved to oppose and attack her. None of their assaults have gained much traction, even by the low standards of last summer’s “wise Latina” inanity.

They have argued that Kagan lacks judicial experience. But so did William Rehnquist when he was nominated to the Court.

They have accused her of being too much of an advocate, but so was Chief Justice Roberts for most of his career.

They have tried to paint her as anti-military for briefly preventing the military from using Harvard’s career services office because of “Don’t Ask, Don’t Tell,” even though she was simply following Harvard Law School’s non-discrimination policy and even though her actions were the same as those taken by deans at many other leading law schools.

They have even criticized her for praising her former boss, and civil rights icon, Justice Thurgood Marshall, mentioning him more frequently than President Obama during the first day of confirmation hearings.

As an aside, in a country where only 2% of the public can name all nine current Supreme Court justices, attacking a nominee for her loyalty to a Justice who died nearly two decades ago is unlikely to get you very far. Even less effective has been the puzzling criticism, echoed by Sen. Grassley on the second day of the hearings, that Kagan was overly effusive in her introduction of retired Israeli Supreme Court justice Aharon Barak when he gave a speech at Harvard.

When these lines of attack predictably failed, Republicans began attacking Kagan for her failure to express strong enough opinions on hot-button issues, which is to say, they have attacked her for not providing them with better raw material for their attacks.

As any lawyer will tell you, when you don’t have any facts to argue, you start to argue about presumptions and burdens of proof.

Thus, it should come as no surprise that in a June 27 column for USA Today, Sen. John Cornyn (R-Texas) said he didn’t need to look for actual evidence that Kagan was an activist who’s outside the mainstream because the burden is on her to prove that she is not. “It is reasonable to worry that Kagan is a judicial activist,” he argued, “simply because President Obama nominated her.” This argument is nothing if not novel.

But Cornyn’s approach sheds more light on his motives and those of his conservative allies than it does on either Kagan or Obama (its actual target).

It provides stark evidence that Kagan’s confirmation hearings have nothing to do with Kagan herself or with her qualifications to serve on the Court, and everything to do with opposition to her nomination for opposition’s sake.

This obstructionist logic will be enough, I suspect, to get all but a handful of Republicans to vote against a seemingly centrist nominee even though they can point to nothing that actually disqualifies her.

Eduardo Penalver is a professor at Cornell Law School.

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