The Supreme Court case Miranda v. Arizona established rights for citizens who are accused of a crime. What is the purpose of giving rights to citizens accused of a crime?

Due process means that laws must be applied fairly and equally to all people, especially to a citizen accused of a crime. The Constitution uses the phrase in the 5th and 14th Amendments, declaring that the government shall not deprive anyone of "life, liberty, or property, without due process of law ... " The 5th Amendment protects people from actions of the federal government, and the 14th protects them from actions by state and local governments.