The "mere act" of the state approving leases doesn't mean there's an imminent threat to the environment, said Barry County Circuit Judge Amy McDowell.
A group called Michigan Air Land Water Defense argued that the Department of Natural Resources first needs to assess the impact of hydraulic fracturing or "fracking." It involves pumping water, sand and chemicals underground to break open shale rock and release natural gas.
The lawsuit mentions leases in the Allegan State Game Area, the Barry State Game Reserve and Yankee Springs Parks and Recreation Area. McDowell said lease holders are not close to moving into a drilling stage.
"The court is not able to consider a violation of the public trust at this time as the DNR has merely issued a non-developmental lease permit," she wrote. "The DNR therefore has not engaged in an activity that has actually harmed the public trust in these resources or is likely to do so."
Attorney James Olson said the group is considering its options.
"We do intend to seek clarification from Judge McDowell because the opinion lacks any reference to law or facts that were presented in the case under the court rules," he said.
The judge last week said her decision only covers state land in Barry County. Other public land is in neighboring counties.