Standing Rock Sioux Tribe fights to enforce pipeline regulations

The Standing Rock Sioux Tribe is urging a federal court to reject efforts to dismiss its lawsuit seeking to halt the Dakota Access Pipeline's operations, arguing federal law requires an easement for pipelines on public land. The tribe contends the U.S. Army Corps of Engineers has failed to enforce key environmental regulations. Republican-led states intervening in the case argue the lawsuit threatens national energy security. A decision is pending.