The essence of any community is determining who is in it and what are its governing values and process. Our governing values are our constitution, which includes a suspicion of governmental power, and provides rights to "persons" in the country. These rights are guaranteed by a process by which the government can arrest us. In the Fourth Amendment, we gave ourselves the right not to be arrested without probable cause that we have committed a crime, and a warrant being issued by a judge. The police, on their own, do not get to arrest us and hold us. We get taken before a judge within 24 hours or 48 hours over a weekend. We can explain things to the judge in a public courtroom.
Legal precedent is reasoning by analogy. Step by step the law develops. In the 1950s-70s, the Supreme Court expanded the Fourth Amendment to limit police power and preserve freedom. In the 1980s until about six years ago, the Court ruled often in favor of the police and contracted the Amendment. We are now seeing a shift in the tide towards civil liberties.