This coming week is the final week the Supreme Court is in session before October. And while much attention is being paid to the gay rights cases before the Court, there are also a critical voting rights case that could shape Congress for decades to come.

In the Voting Rights Act case before the high court, Shelby County, Ala., is challenging the formula under which only some states, mostly in the South, are targeted and must get permission from the Justice Department or a federal court in Washington for any attempt to change voting procedures.

“What’s unique about Section 5 is that we’ve never (before) had a federal statute that singles out particular parts of the country for unique control by the federal government,” said New York University law professor Richard Pildes, a voting rights expert and a legal adviser to the 2008 Obama campaign.

Shelby County’s lawyers argue that the coverage formula, which relies on election data from the 1960s and 1970s to determine which places Section 5 applies to, is outdated.

If the court does strike down Section 5, “the most likely way they’ll do it is to go after the coverage formula,” Steven Shapiro, legal director at the American Civil Liberties Union, told the American Constitution Society meeting. “If the court goes down that road – and I hope they do not – the important takeaway is that’s not the end of the game. That just puts it all back on Congress’s hands.”