Based on the U.S. Supreme Court's 1966 ruling in Miranda v. Arizona, any person taken into police custody must be read their "Miranda" rights before questioning. Essentially, the Miranda rights are based on the Fifth Amendment of the U.S. Constitution, which protects citizens from self-incrimination.
Police must advise anyone in custody that they have the right to remain silent, anything they say can and will be used against them in court, they have the right to an attorney and an attorney will be appointed to them, if they cannot afford one. If police fail to read one's rights, anything one says is considered involuntary and any evidence stemming from that involuntary statement will probably be thrown out in court.
In a recent DUI case, the Georgia Supreme Court ruled that officers do not need to read Miranda rights before asking motorists who are arrested for drunk driving to submit to a Breathalyzer. This decision vacates a Gwinnett County court ruling that said that the failure to read Miranda rights to a motorist Stephen Turnquest, after he was arrested for a DUI but before making him take a breath test, was a violation of his rights under the Fifth Amendment and state statutes.
As a result, the court had ruled that his Breath test results would be suppressed at trial. Our Supreme Court is sending the Turnquest case back to the Gwinnett County Court to consider whether his breath test results should be suppressed on the grounds that the implied consent advisement given to Turnquest by the arresting officer was misleading.