You might check with the Innocence Project
Good luck to you.
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I concur with my colleague that the Innocence Project maybe a good place to start. It is probably too late to file for an appeal as such, but if this is a case before D.C. Superior Court, you can try filing a motion in that court to have a retrial on grounds of ineffective assistance of counsel. You should have an attorney help you with this. My rates are reasonable.