SCOTUSblog has more thoughts on Voting Rights Act decision issued yesterday by the Supreme Court:

Though the Supreme Court by a wide margin today formally declined to resolve a challenge to the constitutionality of Section 5, the reality is far different. The decision unambiguously served notice that the Justices are prepared to invalidate the statute as it stands. Congress is now effectively on the clock: it has the period between now and the date that it decides a follow-on challenge by a covered jurisdiction that is not permitted to “bail out” of the statutory scheme to amend Section 5. If the statute remains the same by the time the next case arrives, the Court will invalidate the statute.

Today’s ruling is thus as much subtext as text. An entire section of the opinion is devoted to the constitutional infirmities of Section 5. There is no counter-point. Nor do any of the Court’s more liberal members issue a reassuring concurring opinion indicating that Section 5 would survive a constitutional challenge - though some surely believe it.
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A failure by Congress to respond to the Court’s opinion will be fatal to Section 5. If a jurisdiction that is unable to “bail out” from the statute’s coverage yet does not have a reasonably recent history brings a challenge to the statute as currently enacted, it will succeed.