## Facts

- Federal authorities investigated Ning Wen for transferring militarily useful technology to the People’s Republic of China without an export license.
- The investigation used communications intercepted under a court-approved order issued pursuant to the Foreign Intelligence Surveillance Act (FISA).
- A jury convicted Wen of violating export-control laws under 50 U.S.C. § 1705(b), and the district court sentenced him to 60 months’ imprisonment.
- Wen moved to suppress evidence derived from the FISA intercept, arguing that once the investigation’s emphasis shifted toward a domestic criminal prosecution, FISA-derived evidence could not be used and the surveillance violated the Fourth Amendment.
- The district court reviewed the FISA application materials in camera, concluded the intercept order was justified, and denied suppression.

## Issues

1. Whether, under post-USA PATRIOT Act FISA, evidence derived from a FISA intercept may be used in a domestic criminal prosecution so long as foreign intelligence collection was a “significant purpose” when the surveillance was authorized.
2. Whether the FISA surveillance violated the Fourth Amendment and, if any defect existed, whether suppression is barred by the Leon good-faith exception.

## Decision

- The Seventh Circuit affirmed the conviction and sentence.
- The court held that the FISA statute requires only that obtaining foreign intelligence be a “significant purpose” at the inception of the intercept, not that it remain the primary purpose throughout the investigation.
- After in camera review, the court concluded the statutory standards for the FISA intercept order were satisfied, so suppression was not warranted under FISA.
- The court rejected the Fourth Amendment suppression claim, reasoning that FISA surveillance is authorized by a judicial warrant and that Leon’s good-faith doctrine prevents exclusion absent materially false or misleading affidavits or an obvious lack of probable cause.

## Legal Principles

- Under amended FISA, the statutory validity of an intercept turns on whether foreign intelligence collection is a “significant purpose” at the time authorization is sought; later shifts toward prosecution do not, by themselves, invalidate the intercept.
- Courts may review FISA application materials in camera to assess statutory compliance for suppression purposes under 50 U.S.C. § 1806.
- Because FISA interceptions are authorized by warrants issued by Article III judges, ordinary Fourth Amendment suppression limits apply, including the Leon good-faith exception.
- Suppression is generally unavailable where officers relied on a warrant unless the supporting materials were materially false or misleading or probable cause was so plainly absent that reliance was unreasonable.

## Conclusion

The Seventh Circuit upheld Wen’s conviction, holding that FISA-derived evidence was admissible in a criminal prosecution because foreign intelligence collection was a significant purpose when the intercept was authorized and, in any event, Leon’s good-faith rule foreclosed suppression of evidence obtained under a judicial warrant.


United States v. Ning Wen, 477 F.3d 896 (7th Cir. 2007)