Is there an anti-defendant bias in some of the evidentiary rulings of the 9th Circuit?

Matta alleges an anti-defendant bias in some of the court's evidentiary rulings. In particular, he objects to the court's exclusion of photographs depicting Matta delivering Christmas presents to his employees, and to the court's refusal to exclude tapes made of Matta's two-way radio conversations and airplane manuals found at Matta's home. The district court's determinations of relevancy are reviewed for an abuse of discretion. United States v. Schaff, 948 F.2d 501, 505-06 (9th Cir.1991).