Can I go to jail for selling a stolen phone without knowing?

Give it back, you do not own what is stolen property as the thief has no ownership interest to convey. You may have an issue as well for,receiving and concealing stolen property. You should seek counsel

It is possible. In CA the law says you must possess stolen property knowing it was stolen to be convicted of possession of stolen property. Theft may be charged if it was recently stolen.

P.C.496 RECEIVING STOLEN PROPERTY 496. (a) Every person who buys or receives any property that has been stolen or that has been obtained in any manner constituting theft or extortion, knowing the property to be so stolen or obtained, or who conceals, sells, withholds, or aids in concealing, selling, or withholding any property from the owner, knowing the property to be so stolen or obtained, shall be punished by imprisonment in a county jail for not more than one year, or imprisonment pursuant to subdivision (h) of Section 1170. However, if the district attorney or the grand jury determines that this action would be in the interests of justice, the district attorney or the grand jury, as the case may be, may, if the value of the property does not exceed nine hundred fifty dollars ($950), specify in the accusatory pleading that the offense shall be a misdemeanor, punishable only by imprisonment in a county jail not exceeding one year. In this statute the key is in knowing. If the DA cannot prove that you knew that the phone was stolen then you cannot be found guilty.

If you convince the police that you are telling the truth about how you got the phone, you should be fine. If you got the phone for less than a third of retail value, in Michigan, it raises a rebuttable presumption that you knew it was stolen.

Yes, you can go to jail for a Larceny charge. You saying that you didn't know it was stolen is a defense and it may very well be successful. The way it works is the Commonwealth (DA) brings charges against you. They then have to prove, beyond a reasonable doubt the elements of each and every charge. If they are successful, then you lose and are found guilty. If your defense is successful, then you are found Not Guilty and are acquitted. That is the process if it goes to trial. Both your lawyer and the DA will have a pretty good idea in most cases whether or not there is sufficient evidence to convict a person on a particular charge. If they are both in agreement that the evidence is strong, then your lawyer may advise you to plead guilty with a better disposition that he/she feels is possible if you are found guilty and then sentenced by a judge. If both your lawyer and the DA agree that the evidence is weak, then they may agree to dismiss or give you a good deal. If they disagree then you will have to decide whether you want to take the risk and go to trial or whether you want to take a plea offer that the DA proposes. Its quite a bit more complicated than just asking if something will happen based on the way you see things. I assure you that the DA will see things differently. Then it's up to you, through your lawyer, to decide how to proceed.

You have to know or reasonably thought it was stolen before you have any criminal intent.

The State merely needs to say that you did know it was stolen, and you can be charged with a second degree felony, a potential but unlikely 15 years in prison. Get counsel.

If you did not know it was stolen, that is a defense. You have to know something is stolen or have a pretty good idea that there is something wrong. But you may need an attorney to defend you.