## Facts

- Billy J. Darst, a Kansas landowner and chicken farmer, set leg traps on poles on his property to stop owl predation on his chickens.
- On October 1, 1988, a Kansas conservation officer observed a great horned owl trapped on Darst’s property and told Darst that taking or killing great horned owls was illegal; the officer advised Darst to contact a federal game officer about obtaining a permit.
- On February 20, 1989, the officer returned and observed another great horned owl trapped on a different pole; Darst stated he had set four traps on four poles and had not contacted the federal officer about a permit.
- Darst was charged with unlawfully “taking” migratory birds (great horned owls) in violation of the Migratory Bird Treaty Act (MBTA), 16 U.S.C. § 703, and regulations including 50 C.F.R. § 21.11.
- At a bench trial before a U.S. magistrate judge, Darst (pro se) admitted he trapped and killed great horned owls on both occasions and admitted he did not obtain a federal permit.
- Darst asserted he had a constitutional right to defend his property as justification for killing the owls.
- The magistrate judge found Darst guilty, imposed a $125 fine, and assessed $25 in costs.
- Darst appealed to the district court, which decided the appeal on the briefs.

## Issues

1. Whether the great horned owl is a properly designated “migratory bird” under 16 U.S.C. § 703 based on its inclusion in the Secretary of the Interior’s list at 50 C.F.R. § 10.13.
2. Whether the MBTA is unconstitutionally overbroad because it criminalizes killing protected birds to defend private property (protecting livestock).
3. Whether 16 U.S.C. § 703 is unconstitutionally vague because “migratory bird” is defined through regulations, including a broad species list.

## Decision

- The district court affirmed the magistrate judge’s judgment of conviction.
- The court held the great horned owl is covered by the MBTA because Congress authorized the Secretary of the Interior to specify protected species by regulation, and the owl is listed at 50 C.F.R. § 10.13.
- The court rejected the overbreadth challenge, concluding the MBTA validly prohibits taking protected birds absent a permit and does not contain a constitutional property-defense exception.
- The court rejected the vagueness challenge, holding that the statutory-regulatory scheme provides adequate notice by identifying protected birds through the published regulatory list.

## Legal Principles

- Under the MBTA, Congress may delegate to the Secretary of the Interior authority to identify protected “migratory birds” by regulation; species listed at 50 C.F.R. § 10.13 are covered for purposes of 16 U.S.C. § 703.
- The MBTA’s prohibition on taking protected birds applies even when a landowner acts to protect domestic animals; absent authorization (such as a permit), property protection does not excuse killing listed birds.
- A statute is not unconstitutionally vague merely because it works together with regulations to define covered species and prohibited conduct, where the combined scheme gives reasonable notice.

## Conclusion

The district court affirmed Darst’s MBTA conviction because the great horned owl was validly covered by the Secretary’s regulatory list, and neither a claimed constitutional property-defense right nor vagueness or overbreadth arguments invalidated the statute’s application to trapping and killing listed birds without a permit.


United States v. Darst, 726 F. Supp. 286 (D. Kan. 1989)