The supreme court's 1991 ruling that a coerced confession introduced during a trial does not automatically taint a conviction if it is a "harmless error" is an example of the court's recent willingness to make exceptions to the requirements of rights.

Miranda rights

Explanation:

 According to the question, the given example is basically refers to the exception for the requirement of the Miranda rights as the it is developed in the year 1996 by the supreme cout of the united state. It was basically created for protecting the amendment rights.

It is also known as Miranda warning as it providing the information for the law enforcement and the different types of officials.

It is one of the type of notification that is given by the police to the criminal suspects at the time of custody.  

Therefore, Miranda rights is the correct answer.