The court has given no timeline for addressing the request, but allowed lawyers for Nebraska and Oklahoma to make merit-based arguments in briefs due May 23.

That means the states can argue the marijuana issue itself, almost as if Nebraska and Oklahoma were already part of the case, rather than restating their reasons for wanting to join as plaintiffs.

"When they said we could be heard on the merits issue ... that's what we wanted to hear," Peterson said Thursday.

It's a different response than the states received from the U.S. Supreme Court last month when it rejected Nebraska and Oklahoma's case without considering the merits.

Then-Nebraska Attorney General Jon Bruning and Pruitt had petitioned the high court to intervene in 2014, the same year Colorado launched recreational marijuana sales.

Lawyers for Pueblo County, named as a defendant in the 10th Circuit case, wrote in response to the new request that Nebraska and Oklahoma are trying to bypass standard procedure and "short-circuit the process" after being denied by the U.S. Supreme Court.