File a motion in the trial court, requesting a new trial and the withheld evidence. Another suggestion is to get an attorney to assist you with this. If you can't afford an attorney on appeal you can request the court to appoint one for you.
I will be happy to speak with you at no cost with a FREE phone consultation if you have a San Diego or California matter. Please call my office at 619-238-1905 or visit my website at www.lawofficeofwilliamdaley.com
I'm unsure why you are representing yourself. Unless the constitution operates differently in CA, you are entitled to counsel (public defender or court appointed) to represent you on appeal. Handling any legal matter pro se is a recipe for disaster, doing so on an appeal is worse.
It's not a Brady violation unless the information was exculpatory (potentially helpful to your case). Exculpatory evidence must be turned over as soon as the prosecution is aware of it. If the evidence was inculpatory (potentially helpful to the prosecution) they are not required to disclose it until 30 days before trial if they intend to use it. If they don't intend to use inculpatory evidence, they don't need to disclose. If this was a Brady violation or the prosecution failed to turn over inculpatory evidence in advance of trial and then used that evidence against you, you definitely have an appealable issue. You need to engage an attorney to sort it all out.
Mere withholding of interviews is not necessarily a Brady violation. Get a quality appellate counsel on your side to assist ASAP.
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