Pierson v. Post

First possession, capture rules, and the administrability of property rights in wild animals.

Post was hunting and pursuing a fox with hounds on unpossessed land. Pierson, knowing of the pursuit, killed and carried away the fox before Post had captured it.

The court held that pursuit alone did not create property in the fox; occupancy required capture, mortal wounding, or otherwise depriving the animal of natural liberty.

The majority adopted a bright-line possession rule grounded in capture rather than pursuit. The rule favored administrability and reduced disputes over uncertain degrees of effort, while the dissent would have credited reasonable prospect of capture to encourage fox hunting.

1. How does the rule allocate entitlements, precaution, information, or bargaining power?
2. Would a different remedy change transaction, error, or enforcement costs?