I have an already indicted agg perjury case where a defendant was under oath on two separate occasions on bond reduction hearings in front of the judge. The first time he said he was in a gang and the second time he said he was not in a gang and had never been in a gang. I have the lie part covered. My question is - how do I prove the materiality?
Who do I call as a witness or what evidence do I need to put on to show it was material if this for some reason were to go to trial?

In the past, we have simply made the judge from the hearing a witness and he testified on the issue of materiality. Presumably, the judge found the membership in a gang a relevant fact for setting bail. Obviously, the same judge can't be that witness and hear the perjury case.

Thanks for your help.