RICHMOND, Va. (AP) — A federal judge has refused to allow a former Virginia attorney general to testify as an expert witness in former Gov. Bob McDonnell’s corruption trial.

McDonnell and his wife, Maureen, are charged in a 14-count indictment with accepting more than $165,000 in gifts and loans from businessman Jonnie Williams in exchange for promoting his products. Their trial is set for July 28.

McDonnell wanted former attorney general Mark Earley to testify that conduct alleged in the indictment isn’t illegal. He also proposed having a defense attorney testify about the value of immunity offered by prosecutors to Williams in exchange for his testimony. U.S. District Judge James Spencer ruled Thursday that such testimony is inadmissible.

The judge also barred testimony by a former judge and some testimony by an accountant.

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