Let's backtrack a bit for something of a bird's eye view of the subject.
First, sovereign immunity is a complex topic and manifests itself in various ways in various circumstances. A comprehensive discussion of sovereign immunity in the United States is well beyond the scope of this thread. If anyone is interested in beginning his (or her) study of the principle, here are links to a couple of articles that might help start him (or her) on the way: "Suing the Federal Government"; and "A Primer on the Doctrine of Federal Sovereign Immunity".
Second, the principle of sovereign immunity does not foreclose suing the government to challenge the validity or application of a law.
Third, we're here discussing only 42 USC 1983, a federal law that under certain circumstances allows suits for damages against government officials (thus limiting sovereign immunity). Other laws or judicial decisions might limit sovereign immunity (e. g., the Federal Tort Claims Act) in other circumstances, but discussion of those laws in also outside the scope of this thread.
But to return to the subject matter of this thread, the law being discussed, 42 USC 1983, is an example of a conscious erosion by government of sovereign immunity. Again, 42 USC 1983 provides:
By expressly permitting suits against government personnel when their conduct amounts to a "deprivation of any rights, privileges, or immunities secured by the Constitution and laws", the statute effectively waives sovereign immunity with respect to that sort of misconduct. And in that way government officials are held accountable for their misdeeds if they deprive one of "any rights, privileges, or immunities secured by the Constitution and laws."
The case law defining Qualified Immunity under 42 USC 1983 is really about defining what conduct is or is not permissible under the Constitution. It is not about escaping liability for wrongful acts. It's about defining when conduct is wrongful and when it is not.
First, sovereign immunity is a complex topic and manifests itself in various ways in various circumstances. A comprehensive discussion of sovereign immunity in the United States is well beyond the scope of this thread. If anyone is interested in beginning his (or her) study of the principle, here are links to a couple of articles that might help start him (or her) on the way: "Suing the Federal Government"; and "A Primer on the Doctrine of Federal Sovereign Immunity".
Second, the principle of sovereign immunity does not foreclose suing the government to challenge the validity or application of a law.
Third, we're here discussing only 42 USC 1983, a federal law that under certain circumstances allows suits for damages against government officials (thus limiting sovereign immunity). Other laws or judicial decisions might limit sovereign immunity (e. g., the Federal Tort Claims Act) in other circumstances, but discussion of those laws in also outside the scope of this thread.
But to return to the subject matter of this thread, the law being discussed, 42 USC 1983, is an example of a conscious erosion by government of sovereign immunity. Again, 42 USC 1983 provides:
Every person who, under color of any statute, ordinance, regulation, custom, or usage, of any State or Territory or the District of Columbia, subjects, or causes to be subjected, any citizen of the United States or other person within the jurisdiction thereof to the deprivation of any rights, privileges, or immunities secured by the Constitution and laws, shall be liable to the party injured in an action at law, suit in equity, or other proper proceeding for redress, ...
By expressly permitting suits against government personnel when their conduct amounts to a "deprivation of any rights, privileges, or immunities secured by the Constitution and laws", the statute effectively waives sovereign immunity with respect to that sort of misconduct. And in that way government officials are held accountable for their misdeeds if they deprive one of "any rights, privileges, or immunities secured by the Constitution and laws."
The case law defining Qualified Immunity under 42 USC 1983 is really about defining what conduct is or is not permissible under the Constitution. It is not about escaping liability for wrongful acts. It's about defining when conduct is wrongful and when it is not.