Yesterday the Supreme Court heard oral argument in the Texas congressional redistricting case. Here's an account from USA Today, and here is one from Slate.com. There's a pretty strong consensus in press accounts that most justices were unswayed by the arguments of the lawyer for the Democrats challenging the plan engineered by former House Majority Leader Tom DeLay and passed by Texas's Republican legislature.
This is the second major redistricting case to reach the Supreme Court in the redistricting cycle following the 2000 census. In the first case, Vieth v. Jubelirir, Chief Justice William Rehnquist and Justices Sandra Day O'Connor, Antonin Scalia, and Clarence Thomas joined in an opinion by Scalia that held that claims that a redistricting plan is unconstitutional because of political gerrymandering are nonjusticiable. Justice Anthony Kennedy, in a separate opinion, argued that some political gerrymanders might be unconstitutional but that the Pennsylvania plan in question was not. Justices John Paul Stevens, Souter, Ruther Bader Ginsburg, and Stephen Breyer dissented but did not agree on a standard for finding gerrymandering unconstitutional.
Over the last 40 years I've examined every congressional redistricting plan closely, and I think that the Scalia opinion got it right. (Here's a similar view from Edward Blum and Roger Clegg on National Review Online.) All courts need to do is to determine whether the plan meets the equal population standarda matter of simple arithmetic. The equal population standard actually imposes a pretty strict discipline on politically motivated redistricters. You can only go so far to benefit your party. And over the 10-year intercensal period when a redistricting plan ordinarily remains in effect, there are likely to be shifts in the contours of partisan support that will tend to frustrate partisan redistricters. This happened in the 1960s, 1970s, 1980s, and 1990s.
For example, in California in the 1990s, coastal areas became more Democratic and inland areas became more Republican. Thus coastal districts that were marginal in 1992 were by 2000 safe Democratic, while inland districts that were marginal in 1992 were by 2000 safe Republican. Safe Republican coastal seats and safe Democratic inland seats became marginal over that period of time.
There have been many lamentations in recent years that the 2000 cycle redistrictings have made too many incumbents safe from challengers. It's true that there was lots of gerrymandering in states with large numbers of seats: Republican gerrymanders in Florida (25 seats), Pennsylvania (19), and Michigan (15) as well as the 2003 DeLay-engineered plan in Texas (32); Democratic gerrymanders in Georgia (13), North Carolina (13), and Maryland (8); and bipartisan incumbent-protection plans in California (53), New York (29), Illinois (19), and Ohio (18). Add those states together and you've got 244 seats, a majority of the 435-seat House. (In 2005 the newly Republican legislature in Georgia passed a partisan redistricting plan replacing the Democrats' earlier plan.)
But all those incumbents will remain protected only if people keep on voting the way they did in 2000 (the last year for which the redistricters, except in Texas and Georgia, had results). They mostly did in 2002 and 2004. We haven't had a change in partisan contours in this decade as we did in the previous four decades. But we have three elections to go in this intercensal cycle. Some Democrats think there may be changes from what have been the prevailing patterns since 1996 in the elections next fall. They may turn out to be right.
In the meantime, a rule that no equal-population plan will be thrown out for political reasons would remove the courts from the inevitably partisan business of redistricting. Justice Kennedy, the swing vote in Vieth, is reported to have been skeptical about overthrowing the Texas plan. My own view is that the Pennsylvania plan in that case was as clearly partisan as any plan I've ever seen, and that if Kennedy couldn't find a basis to overturn that one, he won't be able to find a basis to overturn the Texas plan.
Footnote. The accounts of the justices' questions suggests that the court might overturn at least a few of the district lines on the grounds that they violate the Voting Rights Actor at least the prevailing interpretation of that act which requires maximizing the number of "majority-minority" districts. Counsel for a Latino group argued that the new 23rd District, with a 51 percent Hispanic population, is not Hispanic enough; when asked what Hispanic percentage would be Hispanic enough, the lawyer said it depended on the district. But of course the motivation for this challenge is political: the 23rd District had the effrontery to elect a Hispanic Republican, Henry Bonilla. But who says that Hispanics can be represented only by Democrats George W. Bush carried the 23rd District, as well as the 15th District (69 percent Hispanic), the 27th District (68 percent Hispanic) and the 28th District (64 percent Hispanic).