No. Many people mistakenly believe that a case will be thrown out of court if the police fail to give Miranda warnings to the arrested person. What Miranda actually says is that a warning is necessary if the police interrogate a suspect and want to use any of her responses as evidence. If the police fail to give you a Miranda warning, nothing you say in response to the questioning can be used as evidence to convict you.
In addition, under the "fruit of the poisonous tree" rule, if the police find evidence as a result of an interrogation that violates the Miranda rule, that evidence is also inadmissible at trial. For example, if you tell the police where a weapon is hidden and it turns out that you gave this information in response to improper questioning, the police will not be able to use the weapon as evidence unless the police can prove that they would have found the weapon without your statements.
Proof & Defenses in Criminal Cases
Getting a Lawyer for your Criminal Case
Steps in a Criminal Defense Case
Arraignment: Your First Court Appearance
Plea Bargains (Deals) in a Criminal Case
Legal Elements of Common Crimes
Expungement & Criminal Records
Should I just plead guilty and avoid a trial?
Is the public defender a real lawyer?
Can I change defense lawyers after I've hired one?
How long after arrest do I find out what the charges are?
Does it matter whether a suspect is given the Miranda warning?