Arguments before the Supreme Court on Tuesday left affirmative action supporters more optimistic than they expected to be that a Michigan ban on racial preference programs might be struck down.

Several justices gave more credence than expected to the argument that by banning affirmative action through an amendment to the state constitution, Michigan had unfairly made it more difficult for minorities to change the policy than non-minorities trying to push analogous kinds of change. The 2006 amendment, known as Proposal 2, forbids using “preferential treatment” based on race, gender or ethnicity in state education, employment or contracting

Mark Rosenbaum of the American Civil Liberties Union in Southern California told the justices that a minority applicant to a Michigan state university who wanted to invoke racial diversity as a reason for being admitted would be “shown the door”—and be forced to mount a costly campaign to undo the amendment. Someone wanting to use a parent’s alumni status as a reason for admission, on the other hand, would be able to press his or her case easily through the admissions process or the Board of Regents. “It creates two playing fields,” Rosenbaum said.

The optimism of affirmative action supporters was boosted by the fact they only need four votes—not the usual five—to achieve their goal in the case, titled Schuette v. Coalition to Defend Affirmative Action. Justice Elena Kagan is recused as a result of her involvement in 2009, as solicitor general, in deciding whether to file a brief when the Michigan case was before the U.S. Court of Appeals for the Sixth Circuit.

With only eight justices sitting in the case, a 4-4 tie would mean that the Sixth Circuit decision striking down the Michigan ban would stand.

“We have a fair chance of at least four votes,” said Steve Shapiro, the ACLU’s longtime legal director, after the arguments. Based on the questioning, the four who might vote to strike down the ban would be Justices Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor and Anthony Kennedy—though Kennedy’s support is far from certain.

Kennedy actively questioned both sides, but he seemed to weigh seriously the point that a constitutional amendment like Michigan’s was so permanent that it was almost impossible for minorities to seek a change in the policy.

The case turns on a little-known line of Supreme Court cases that have rejected government efforts to restructure the political process in ways that make it harder for minorities to press for change. The leading case is the 1969 decision Hunter v. Erickson, which struck down an amendment to the city charter of Akron, Ohio, that forced any proposed changes to fair housing laws to be put to the voters for approval. The measure placed “special burdens on racial and religious minorities within the governmental process by making it more difficult for them to secure legislation on their behalf,” the court ruled.

Michigan Solicitor General John Bursch repeatedly attacked the line of cases and asserted they could not apply to the Michigan amendment because it seeks to end different treatment between races. “It does not violate equal protection to require equal treatment,” he said.

Justice Sotomayor pounced on Bursch’s arguments early and often, making it clear that she thinks the Michigan ban should be struck down under the Hunter line of cases. Michigan, she said, has told those promoting diversity that “you can’t go to the remedy that works,” namely affirmative action.

Bursch pushed back, arguing that statistics give a “muddy picture” of the impact of Michigan’s ban on diversity at state universities. “It’s not clear that diversity has gone down” at the University of Michigan, he said.

Chief Justice John Roberts Jr. also made his views clear, continuing his hard line against affirmative action. At one point he said opponents of the Michigan ban based their arguments on the premise that affirmative action is “beneficial” to minorities.

“What if the question of whether it’s a benefit to the minority group is more open to debate?” he asked. He then cited by name the so-called “mismatch theory” espoused by Stuart Taylor Jr. and Richard Sander in a 2012 book about affirmative action titled Mismatch. The book argues that affirmative action programs have often placed minority students in universities and classes where they are more likely to fail because of shortcomings in their prior education.

Detroit lawyer Shanta Driver, arguing for supporters of affirmative action, replied, “Certainly the minority voters of Michigan believe” that such programs are beneficial, noting that 90 per cent of black voters voted against Proposal 2.

When Justice Antonin Scalia agreed with Roberts that the benefit of affirmative action is “a debatable question,” Driver shot back. “It’s a debatable question in another forum and in a different case, and in fact I think that case was the Grutter case,” she said. Driver was referring to Grutter v. Bollinger, the 2003 case that upheld affirmative action programs as a method to increase diversity at the University of Michigan—a precedent that the court cited as “given” in its affirmative action decision just last term, Fisher v. University of Texas.

The appearance of Driver, a partner at the Detroit firm Scheff, Washington & Driver, was a surprise to many lawyers involved in the case. Until late last week George Washington, her partner at the firm, was scheduled to argue on behalf of the coalition defending affirmative action. But on Friday, Driver informed the court she was arguing instead. She could not be reached for an explanation. Driver also serves as national chair of the group she was representing—the Coalition to Defend Affirmative Action, Integration, and Immigrant Rights and Fight for Equality by Any Means Necessary (BAMN).

It was also unusual that two lawyers, not one, argued on behalf of plaintiffs who challenged the Michigan ban. Rosenbaum represented the so-called Cantrell plaintiffs, a group of students, faculty and prospective applicants to Michigan’s state universities, while Driver argued for the coalition.

In a September 6 motion seeking divided time, Rosenbaum told the court that the two plaintiff groups had distinct and “in some respects, seriously incompatible” positions on the theory of the case. As the arguments played out, however, there appeared to be little distance between their two positions.

Contact Tony Mauro at tmauro@alm.com.