By her ruling, Judge Rosemary Collyer agreed that advocates could proceed with their claim.
The battle over the West Douglas herd is nearly two decades old, and only through the efforts of concerned citizens and organisations have the horses been saved from the BLM's desire to remove them all from their homelands.
In 2009, opponents won the first case in the United States against the bureau's practices of eliminating wild horse herds when Judge Collyer set aside the department's 2008 roundup plans.
In 2010 advocates again sued the bureau and it withdrew its plans to cut the herd.
"The court agreed that we have the right to challenge the decision to zero out the herd, originally made in the 2005 Amendment, despite the fact that the BLM has decided not to perform a round up and removal in 2010," said Bruce Wagman of Schiff Hardin LLP, legal lead for the groups.
"BLM has been trying to avoid the issue with self-serving tactics, but the court found the BLM's decision to hold off on this year's gather 'does not effect any change to the allegedly improper decision to eliminate the herd as soon as practicable'. This is, of course, exactly what we argued."
Co-counsel Valerie Stanley said: "For years, BLM has issued cookie-cutter environmental assessments that purport to elicit public opinion on whether wild horses and burros should be removed from the public lands, all the time knowing that they set these eradication decisions in stone years previously.
"BLM has finally been called on their game plan to decimate the nation's wild horses and burros."
R.T. Fitch, president of the funding organization, the Wild Horse Freedom Federation, said: "We have made a commitment to not only the wild horses but to the American public, that we are in this battle for the long haul and will stand firm on the letter of the law until the BLM relents and agrees to follow its mandates."
Hilary Wood, of Front Range Equine Rescue, added: "While the fight to preserve wild horses is far from over, this 'win' provides hope that justice can prevail in the courts for America's mustangs."
Plaintiffs in this action include, Habitat for Horses, Front Range Equine Rescue, The Cloud Foundation, Colorado Wild Horse and Burro Coalition, Dr Don Moore, Toni Moore and Barbara Flores who are collectively supported by the Wild Horse Freedom Federation.