No, the case does not get dismissed because he did not give you your Miranda rights. Whether you have a viable Motion to Suppress is something you need to discuss with an experienced NM criminal defense lawyer. Good luck.
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Miranda v. Arizona has served as the touchstone for the exploration of the scope of that privilege during a period of custodial interrogation. Our Fifth Amendment to the United States Constitution guarantees to all people the privilege to be free from compulsory self-incrimination.
Anything you said once in custody may be subject to being suppressed.
Just because you were not read Miranda Rights does not mean the case automatically gets dismissed. I agree with my colleage Mr. Bailey.
The Court in Miranda in 1966 created right to counsel procedural safeguards to adequately ensure that the accused know their rights and that the police honor them. The Miranda Court recognized that "[a]n individual swept from ... familiar surroundings into police custody, surrounded by antagonistic forces, and subjected to ... techniques of persuasion ... cannot be otherwise than under compulsion to speak."
Online we cannot know what the other details are going on in your case because online we cannot find out those details. You need a lawyer. Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
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