In the case of Kelley, Commissioner, Suffolk County Police Department v. Johnson in 1975, the U.S Supreme Court ruled on a matter concerning personal liberties versus government regulation. A police officer from Suffolk County challenged a departmental regulation that limited the length of an officer's hair. The plaintiff argued that this policy violated his constitutional rights to liberty as protected by the Fourteenth Amendment’s Due Process Clause. However, the Supreme Court disagreed and upheld the department's grooming standards for its officers. The court reasoned that such regulations were within governmental authority when they are reasonably related to legitimate state interests - in this case maintaining discipline and uniformity within a police force. It was held that unless it could be proven beyond reasonable doubt that there was no rational connection between these regulations and their stated purpose, they would stand lawful under constitution scrutiny. This decision reinforced governments' power to regulate physical appearance for certain public employees when justified by relevant professional considerations or needs.

In the dissenting opinion for Kelley, Commissioner, Suffolk County Police Department v. Johnson (1975), Justice Brennan disagreed with the majority's decision to uphold a police department regulation limiting how its officers could wear their hair. He argued that such personal appearance regulations should be subject to strict scrutiny under the Fourteenth Amendment's Due Process Clause because they infringe on an individual’s liberty interest in choosing his or her own personal appearance. According to Justice Brennan, this is not a trivial matter but rather one of great importance as it involves an individual’s freedom of expression and identity. The state must therefore show compelling reasons for imposing such restrictions and demonstrate that they are narrowly tailored to achieve those ends. In this case, he did not believe that maintaining discipline within the police force was sufficient justification for restricting officers' rights in such a manner.