What is the current state of the law on "mere proximity" defense in a criminal case?

"In general, a defendant is entitled to have the judge instruct the jury on his theory of defense, provided that it is supported by law and has some foundation in the evidence." United States v. Duran, 59 F.3d 938, 941 (9th Cir.) (internal quotations omitted), cert. denied, 116 S.Ct. 535 (1995). However, "[a] defendant is not entitled to any particular form of instruction, nor is he entitled to an instruction that merely duplicates what the jury has already been told." United States v. Lopez-Alvarez, 970 F.2d 583, 597 (9th Cir.), cert. denied, 113 S.Ct. 504 (1992). It is not reversible error for a district court to reject a defendant's proposed jury instruction on his defense theory if the other jury instructions, in their entirety, adequately cover the defense theory. Duran, 59 F.3d at 941.

The "mere proximity" defense theory is a defense to the charge of constructive possession. In United States v. Terry, 911 F.2d 272, 279 (9th Cir.1990), we have held that "[m]ere proximity to contraband, presence on property where it is found and association with a person or persons having control of it are all insufficient to establish constructive possession." (quotations omitted). The defendant's knowledge of the presence of the contraband is a necessary element of constructive possession. Id. at 280.