For claims arising from either of the federal statutes at issue, a suit against an officer of a state legislature in their official capacity, and in which the state is not named in the action, is against the legislator personally in their legislative capacity and doesn't implicate state sovereign immunity.
If Congress can abrogate conduct-based legislative immunity, as opposed to status-based sovereign immunity, a clear statement to that effect in the law is required.
State legislature did not waive its officers' legislative immunity from disability related discrimination claims by accepting federal funds for the legislative session costs pursuant to a federal statute with an antidiscrimination clause.
Legislative immunity bars a suit against a state officer where the injunctive remedy would effect a change in the rules that was more than merely casually or incidentally related to legislative affairs.
Legislative immunity under the Speech and Debate clause can't be limited by the state's adoption of a less expansive standard in its own law.
Extraordinary exceptions to legislative immunity aren't available, since, among other reasons, the legislature was following independent procedural rules, rather than changing them.
DISSENT:
Purpose of the immunity is to prevent the disenfranchisement of the people. Effective ouster and disenfranchisement of some can't therefore be immunized in the interests of protecting others. Only immunizing conduct that isn't facially discriminatory opens the door to facially neutral but discriminatory rulemaking.