In the case of Mt. Healthy City School District Board of Education v. Doyle, a teacher's First Amendment rights were examined in relation to his dismissal from employment. The teacher, Mr. Doyle, had shared with a local radio station an internal memo about teacher dress code which was later broadcasted publicly causing some controversy for the school district. Subsequently, he was involved in an altercation with another staff member and as a result, his contract wasn't renewed by the board citing these incidents as reasons for their decision. Doyle sued alleging that his non-renewal was due to him exercising his First Amendment rights when he disclosed information about the dress code policy to the radio station - thus violating constitutional law. The Supreme Court ruled that if it could be proven that Doyle would have been dismissed regardless of whether or not he exercised those rights (i.e., based on other factors such as misconduct), then there wouldn’t be any violation against him constitutionally speaking; however if it’s shown that this action played substantial part in influencing their decision then they’d indeed violated his First Amendment Rights.

In the dissenting opinion for Mt. Healthy City School District Board of Education v. Doyle, Justice William Brennan disagreed with the majority's decision to remand the case back to lower courts for further proceedings. He argued that there was already sufficient evidence on record to conclude that Doyle's protected speech was a "substantial" or "motivating" factor in his dismissal from employment by the school board and thus, it violated his First Amendment rights. Furthermore, he contended that even if other factors contributed to this decision, as long as one reason is constitutionally impermissible (like retaliation against free speech), then such action cannot be justified under any circumstances. Therefore, according to him, no additional hearings were necessary and Doyle should have been granted relief immediately.