What happens if i was never read my miranda rights?

1. Miranda only applies if it was law enforcement representatives who question you.  Your question is not clear whether it was a store security officer or the police who questioned you. 2.  You could be charged under an accountability theory.  Think of it like being a bank-robber. You helped them steal, by handing them something from the shelf.  3.  Miranda generally kicks in if you are considered "in custody".  If Officers show up and ask, "Hey what happened, we are conducting an investigation", they do not necessarily need to read Miranda.  The idea that Miranda rights need to be read the second the cops put the handcuffs on you is a fiction of television.  If they arrest you and then decide to do a custodial interrogation, then you should be read your Miranda rights. 4.  A violation of Miranda would result in the suppression of the evidence, in your case, any inculpatory statements you may have made.  However, that does not mean there is insufficient evidence to convict you.  For example, if your buddy decides to say, "Yeah, he was working with me and he handed me the item", the evidence of your buddy's statement and the evidence he had stolen goods on him is not suppressed.  Only evidence that comes from your statement is suppressed.