When will the exclusionary rule be applied in immigration proceedings?

When reviewing whether evidence is tainted by a suppressible violation in the criminal sphere, we employ a burden-shifting framework. In that context, "[i]nitially, the defendant who shows that he was the victim of an unconstitutional search must go forward with specific evidence demonstrating taint. The burden then shifts to the government to show that it acquired its evidence from an independent source." United States v. Cella, 568 F.2d 1266, 1284-85 (9th Cir. 1977) (citations omitted). We adapt that framework for our purposes here. Applied to the limited instances in which we recognize the availability of the exclusionary rule in immigration proceedings, if an alien establishes a prima facie case of an egregious regulatory or Fourth Amendment violation warranting suppression, the alien is then charged with providing specific evidence that each piece of allegedly suppressible government evidence is tainted by that unlawful act. Upon that showing, the burden then shifts to the government to contest the alien's specific evidence of taint or otherwise show the government's allegedly tainted evidence is immune from suppression, including a demonstration that the evidence was obtained independently of or is sufficiently attenuated from the underlying unlawful act or evidence obtained therefrom.