"Congress can impose this disparate treatment forever because of the history in the South?"

Chief Justice Roberts in argument in the Voting Rights Act case, which Dahlia Lithwick summarizes — with unusually labored breeziness — here.

[Justice Scalia] insists that the judgment of Congress is not to be trusted because when it came to reauthorizing the Voting Rights Act, "they get elected under this system. Why should they take it away?" Oh. My. God. You mean legislators are self-interested!?! That must mean the court is free to substitute its judgment for that of Congress.

This is a too-cheap laugh for Lithwick. Obviously, this is not a typical case for deferring to Congress. The challenged law structures the election of members of Congress, and it applies to some states and not others.

Debo Adegbile is in the case representing the NAACP Legal Defense Fund. When he reminds the court that "Congress is permitted to use so much of its power as is necessary" to remedy racial discrimination, the Chief Justice clobbers him with: "Is it your position that today Southerners are more likely to discriminate than Northerners?" When Adegbile replies that the covered states tend to be repeat offenders in this area, Roberts comes back with, "So your answer is yes?"

Scalia asks Adegbile what the vote was when Congress reauthorized Section 5 in 2006.

Answer: 390-33 in the House, 98-0 in the Senate. Scalia retorts that "the Israeli Supreme Court, the Sanhedrin, used to have a rule that if the death penalty was pronounced unanimously, it was invalid, because there must be something wrong there." (And before you liberals start crowing that Scalia is citing foreign law, let it be noted that he is citing religious law, which is totally cool and different than foreign law.) Today Scalia seems to have fashioned a new constitutional principle: The courts should always defer to Congress unless Congress is unanimous, in which case Congress is a sack of self-interested liars. Fascinating.

Well, think about it. They're all there — from all the states — and they all got elected under the existing system, a system that is not uniform among the states. Doesn't that mean something?