The Ninth Circuit's decision stands in stark contrast to Coker v. Whittington, No. 16-30679 (May 23, 2017), in which the Fifth Circuit held that the defendant did not violate the constitutional rights of two sheriff's deputies when it fired them for violating its Sheriff's Code of Conduct by moving in with each other's wife and family before getting divorced from their current wives. (See this post.) Although the Coker case presents somewhat different facts, the deputies, like Perez, were allegedly fired for private sexual conduct that was perceived as being immoral, so they may very well have fared better in the Ninth Circuit.
Despite the Ninth Circuit's narrow approach, police departments presumably would have some discretion to discipline officers for inappropriate sexual conduct. For example, sexual conduct between an officer and a suspect being investigated by the officer might be seen as affecting job performance. Similarly, a department might be able to justify a policy that limits sexual conduct between a supervisor and a subordinate.
This blog reflects the views solely of its author. It is not intended, and should not be regarded, as legal advice on how to analyze any particular set of facts.