A public employee’s speech is protected only in defined circumstances, and the analysis proceeds in steps.
Was the employee speaking as a citizen or pursuant to official duties? Speech made pursuant to official duties receives no First Amendment protection in the employment context, however important its subject. Duties are assessed practically, not by job description alone.
Was it on a matter of public concern? Determined by content, form and context. Complaints about personal working conditions and internal grievances generally are not; allegations of corruption, misuse of public funds and public safety generally are.
Balancing. The employee’s interest in speaking against the employer’s interest in efficient public service — disruption, undermining of authority, impairment of working relationships and of the employee’s ability to perform.
Causation and the same-decision defence. The speech must have been a substantial or motivating factor, and the employer may show it would have acted regardless.
Reporting internally. Speech through the chain of command is more likely to be treated as pursuant to duties; the same content in a public forum may be protected. That distinction is uncomfortable and is the law.
Statutory whistleblower protections frequently reach further than the constitutional claim and should be assessed alongside it.