Last week in Pool v. City of Houston, the Fifth Circuit confronted a "zombie statute"--a law that nominally remain in the law books even though they are unenforceable after having been found unconstitutional. (There are dozens of such laws across the country, including many old Jim Crow-era segregation laws, as well as the ordinance against same-sex marriage that was struck down in Obergefell v. Hodges.)
The plaintiffs, who wanted to circulate petitions in Houston to begin the citizen referendum process, had standing to sue about an unconstitutional restriction on their rights even though the Supreme Court had struck down a similar law 20 years ago.
In the words of the Court, given Houston's actions towards the plaintiffs: "This zombie shows signs of life."