Arguments in a federal lawsuit contesting the roundup of hundreds of wild horses in western Wyoming last fall will focus on a federal law that carries different rules for private and federal land.
The 1,263 horses gathered in late September and early October roamed both types of land in a vast area of sagebrush desert featuring square-mile sections of private land interspersed with equal-sized sections of federal land.
U.S. District Judge Nancy Freudenthal will consider Monday whether the U.S. Bureau of Land Management violated the Wild Free-Roaming Horses and Burros Act with the roundup in the Checkerboard area east and south of Rock Springs.
The act requires the BLM to maintain sustainable populations of wild horses on public land and to round up wild horses from private land when a landowner requests it.
The problem is few fences separate the Checkerboard's public and private lands. Wild horses — descendants of domestic horses that have run loose since the days of the Spanish explorers — crisscross the public-private land boundaries at will.
The BLM went ahead with last year's roundup after the U.S. 10th Circuit Court of Appeals refused to block it at the request of wild horse advocates.
The American Wild Horse Preservation Campaign and others continue to press a lawsuit they filed last summer against Interior Secretary Sally Jewell. They claim the roundup violated several federal laws.
The groups claim the BLM neglected to determine beforehand that the Checkerboard herds contained excess animals, and failed to conduct an environmental analysis required for any roundup that would reduce a herd below a pre-established minimum size.
Both are requirements under the wild horse and burro act for roundups on public land.
"BLM is not at liberty to pick and choose which statutory mandates to comply with based on what makes BLM's task easier," the groups state in their opening brief.
The federal government counters that the BLM followed the law in conducting the roundup at the request of the Rock Springs Grazing Association. The ranchers group sued in 2011 to force the BLM to remove all wild horses from the association's lands, including the Checkerboard lands, in accordance with the wild horse and burro act.
The BLM resolved the lawsuit in 2013 by generally agreeing to the demands. After one roundup, the BLM returned some horses to the range then prepared to remove all wild horses from Checkerboard lands within three herd management areas.
The BLM determined that the roundup would meet its legal obligation to the landowners request and it could proceed without in-depth environmental analysis, according to the government's brief.
The agency acted legally and any remaining questions about it are moot, the government's brief states.
The Rock Springs Grazing Association and state of Wyoming have intervened in the case on the federal government's side. Wyoming in December filed a separate federal lawsuit alleging the BLM hasn't done enough to reduce wild horse numbers.
Freudenthal typically presides in Cheyenne but will hold this hearing at the University of Wyoming College of Law in Laramie.
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