Under the inevitable discovery exception to the exclusionary rule, evidence is admitted, even if it's the fruit of an unconstitutional search, if the government would have discovered the evidence through constitutional means if the unconstitutional search hadn't occurred. The basic idea is what lawyers call a "but for" causation principle: If the constitutional violation didn't cause the discovery of the evidence, the public shouldn't be worse off (made so by useful evidence being suppressed) just because a constitutional violation occurred.
Last week's decision by the Tenth Circuit in United States v. Streett considers whether the inevitable discovery exception applies when the government obtains a defective warrant—in this case, a warrant based on an affidavit that lacked probable cause. The government argued that inevitable discovery applies because they would have done better the second time if the magistrate judge had pointed out their error. If the magistrate judge had spotted the error in the warrant affidavit, the government argued, investigators would have corrected the mistake and submitted a proper affidavit. In that case, agents would have obtained a constitutional warrant and the search would have been constitutional. Given that investigators would have responded to the magistrate judge's pointing out the defect by submitting a proper application, the inevitable discovery exception should apply.
The Tenth Circuit agreed with the government's argument, rejecting the defendant's three arguments that the inevitable discovery exception did not apply in these circumstances:
