HuffPo has more information on the gerrymandering case involving the Democrats in Maryland:
On Wednesday, the Supreme Court will hear a challenge from Republican voters in the 6th District who say state officials violated the U.S. Constitution in redefining the district’s borders. The plaintiffs argue that by drawing the boundaries based in part on political data, Democrats essentially punished voters for their past support of GOP candidates, violating their First Amendment rights. …
The Maryland case is different from the Wisconsin one in a few key ways. While the Wisconsin lawsuit challenges an entire map, the Maryland suit seeks to redraw just one district (though obviously that would affect other districts). The Maryland case is being brought by Republicans, who were the main beneficiaries of congressional gerrymandering after the 2010 Census. And the Maryland plaintiffs are advancing the novel legal idea that partisan gerrymandering amounts to an unconstitutional retaliation based on voters’ past choices.
A district is unconstitutional, they contend, when officials take voters’ past support for candidates into account and draw a map in such a way that dilutes their votes with no justification other than partisan gain. Richard Pildes, an election law expert and professor at New York University, wrote in a blog post that the plaintiffs were suggesting a way to evaluate partisan gerrymandering claims that is similar to the way the Supreme Court already looks at claims of race-based gerrymandering ― an area of law the court is active in.
An interesting legal assertion, although since people are changing domiciles from time to time, the idea that they’re being punished for past voting patterns seems a trifle dubious to me.