You can find the collection of briefs here. There are a number of notable briefs, including this brief from the Brennan Center, Demos, Lori Minnite, Project Vote and PFAW on the absence of evidence of impersonation voter fraud; this brief from three current and two former secretaries of state; this brief from Sen. Feinstein and Reps. Brady and Lofgren; and a number of academic briefs including: this brief by Professors Michael Alvarez, Lonna Rae Atkeson, Delia Bailey, Thad Hall, and Andrew Martin on voter id and turnout; this brief by 29 prominent historians and social scientists who write in the area of race and politics; this brief from Professors Chris Elmendorf and Dan Tokaji on the appropriate legal standard for evaluating these cases (my own brief on the subject, filed earlier with co-counsel Schulte Roth and Zabel is here); this brief on behalf of Frederic Schaeffer, Louis Massicote, Toby Moore, Graeme Orr, and others, argues that the requirements in other countries do not provide support for Indiana’s voter ID law; and this brief by Professor Erwin Chemerinsky in support of neither party on the appropriate legal standard.
In conjunction with the filing of the amicus briefs, the Brennan Center issued a press release, New Study Finds African Americans, Low-Income Voters, Students and Seniors Least Likely to Have Valid Voter ID at Issue Before Supreme Court. It links to this new study by Professors Barrett, Nuno and Sanchez. See also this AP report.
The state’s brief is due in early December.