It's called Walker v. Texas Division, Sons of Confederate Veterans, Inc.
Here's the question presented to the court:
Issue: (1) Whether the messages and images that appear on state-issued specialty license plates qualify as government speech immune from any requirement of viewpoint neutrality; and (2) whether Texas engaged in “viewpoint discrimination” by rejecting the license-plate design proposed by the Sons of Confederate Veterans, when Texas has not issued any license plate that portrays the confederacy or the confederate battle flag in a negative or critical light.
Here's a description from ScotusBlog:
The Supreme Court agreed this afternoon to rule on a state government’s power to set up a specialty license plate program that controls the messages that may be displayed. It accepted for review an appeal by the state of Texas, seeking to defend a state agency’s refusal to allow an organization to use a Confederate flag on a specialty plate because it found that display offensive.
. . . The key issue in the license plate case (Walker v. Sons of Confederate Veterans) is whether the messages that are displayed on specialty tags are a form of government speech, so that officials can decide which to allow or to forbid. If, however, they represent the views of the car or truck owner, then the government’s power to veto a message is more tightly restricted.
In a 1977 ruling, in Wooley v. Maynard, the Court treated a license plate message as a form of private speech displayed on private property, but it did not rule explicitly whether this was government speech or private speech more generally. In the 2009 decision in Pleasant Grove City v. Summum, the Court decided that a government entity has a right to speak for itself, and thus has the authority to refuse to accept a symbolic monument for display in a public park.
The Court was asked in the Texas case, and in a separate North Carolina case that is now apparently being kept on hold, to clarify a split among federal appeals courts on whether vanity plate messages are to be treated as government or private expressions. In the Texas case, a group that seeks to preserve the memory and reputation of soldiers who fought for the Confederacy sought state approval for a plate design that included the Confederate battle flag.
Ultimately, after a series of conflicting votes, a state agency turned down that design, saying that many people regard the rebels’ flag as associated with hatred toward groups. The Texas Division of the Sons of Confederate Veterans sued, and ultimately won a decision by the U.S. Court of Appeals for the Fifth Circuit, declaring that specialty plate messages are a form of private speech, and that the state agency had engaged in forbidden viewpoint discrimination.
Sounds fun, here's info from other sources:
NYT: Supreme Court to Hear Cases on License Plates and Mentally Disabled Death Row InmatesWP: Supreme Court to hear Confederate-flag license plate case from Texas.