On Monday, the Supreme Court heard oral arguments in the case of United States v. Texas, a challenge to President Obama’s 2014 executive action on immigration. Specifically, the case concerns the Deferred Action for Childhood Arrivals (DACA) and Deferred Action for Parents of Americans and Lawful Permanent Residents (DAPA) policies. These policies would allow certain undocumented immigrant children and certain undocumented immigrant parents of citizen children to remain in the United States, respectively. The Court will decide whether these policies exceeded the executive branch’s authority by skirting the immigration laws passed by Congress.

In many ways, the oral arguments in United States v. Texas defy the standard format of Supreme Court proceedings. While there are traditionally two advocates, each speaking for 30 minutes, there were four advocates who argued on Monday for a grand total of 90 minutes. On the petitioner’s side (arguing in favor of DAPA/DACA), Solicitor General Don Verrilli represented the federal government (namely, the executive branch) and argued for 35 minutes. Then, an attorney from the Mexican-American Legal Defense and Education Fund (MALDEF) argued for 10 minutes on behalf of unauthorized immigrant women who would benefit from DAPA. These women were intervenors in the case, which means that, although they were not initially parties to the suit in the district court, they were parties who were likely to be directly affected by the outcome of the case. After the Fifth Circuit Court of Appeals granted an injunction preventing the federal government from implementing its immigration policy, these intervenors asked the Fifth Circuit to let them take part in the case because of the decision’s effect on them. That court granted their motion, and under Supreme Court Rule 12.6, any party in the lower-court proceedings becomes a party in the Supreme Court. Because the outcome of the case will fundamentally affect the lives of undocumented immigrants, it made sense that the Court would choose to hear arguments from these parties before making a determination.

Meanwhile, for respondents, Texas Solicitor General Scott Keller represented the states suing the Obama administration and received 30 minutes of time for argument. An attorney representing the House of Representatives spoke for 10 minutes. The House of Representatives was an amicus curiae (Latin for “friend of the court”) in the case, which means it was not a party to the litigation but had an interest in the outcome. Amici curiae are common in Supreme Court cases, with amici filing an average of 11 briefs per case, but it is fairly rare for the Court to permit an amicus to argue before the Court. (For example, in his book Oral Argument and Amicus Curiae, Matthew Roberts concludes that amici are granted time at oral argument in less than 8 percent of cases per year on average.) Yet Congress files amicus briefs fairly frequently and is granted time at oral argument as a matter of custom. (For example, in 2012, when the Obama administration refused to defend the Defense of Marriage Act in United States v. Windsor, an advocate for the Bipartisan Legal Advisory Group of the House of Representatives was allowed to argue in favor of the law.) In a case such as United States v. Texas, giving a voice to Congress makes sense – at bottom, the Court is deciding, in part, whether the executive can form its own de facto immigration policy or whether only Congress can set such priorities. Congress, therefore, may be more affected by the outcome of this decision than even the states, whose interest in the case has so far been framed as the expense Texas would suffer if it had to issue driver’s licenses to individuals granted some type of quasi-legal status under DAPA and DACA.

United States v. Texas could be “the most important case the Court will decide this year.” The decision may affect the separation of powers between the executive and legislative branches, federalism (the division of power between the states and federal government), and the legal status of millions of individuals. Accordingly, the Court wisely chose to hear from as many affected groups as possible. Yet all of this may be for naught – after oral arguments, many commentators suggested that the Justices appeared to be split 4-4 along ideological lines. If so, the lower court’s decision will stand –meaning that Obama’s immigration initiatives will be blocked – and the legal questions will receive no definitive answers. Thus, despite the Court’s best-laid plans, United States v. Texas may join other cases of the 2015-16 term that, because of a divided bench, leave many interested parties in limbo.

Contact Alex Twinem at atwinem ‘at’ stanford.edu, Brittany Jones at bjones2 ‘at’ stanford.edu, Danny Kane at dkane ‘at’ stanford.edu, and Michael Qian at mfqian ‘at’ stanford.edu