It could be....mistakes can happen, throughout our justice system...and due process, whether simply a court hearing or a full blown trial depending on the alleged crime, can limit the Human error or govt mistakes. It's more important to not take the liberty away from an innocent man, than it is to punish a guilty one....is how our whole justice system is created....
Miranda rights
Warrants for search and seizures
Subpoenas for testimony
Due process rights,
Right to an attorney
Right to a speedy trial
Habeas corpus
And s verbal other things not mentioned are all to protect the innocent.
Some times, it may help the guilty, like cops forgetting to give the criminal their Miranda rights....