The answer is maybe. It depends if the court believes the third party was acting as an agent of the police and at their direction, if so, it is possible you may be able to raise an entrapment defense. You will also have to deal with the lapse in time between your conviction and your request for relief.
I agree with the previous answer but would add that it is water under the bridge since your motion was set aside. Unfortunately, this is something that should have been evaluated before you entered your plea. Entrapment is a very hard defense to prove, however.
Entrapment is a complex defense to analyze and to prove. I'm more concerned with the passage of time--it will be very difficult undo what has already transpired. In fact, that it probably a bigger challenge than the entrapment defense at this point.
Appealing a 1989 conviction us going be be way tough.
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There is no such thing as "vacating" a conviction. If you truly have strong new evidence, you might be able to get the conviction overturned and a new trial. If you are acquitted at your new trial, you will have no criminal conviction. But, as the other attorneys on this thread have indicated, getting a new trial on such an old conviction will be very difficult. It will require showing very strong new evidence that you had no way of bring to light at any earlier time. Since you say the motion was denied, it sounds like you do not have this.
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