In a brief filed Wednesday, the US Solicitor General urged the Supreme Court to dismiss a lawsuit by the states of Nebraska and Oklahoma against Colorado's marijuana legalization law.

The two states had filed the lawsuit in December 2014, complaining that "the State of Colorado has created a dangerous gap in the federal drug control system" and that "marijuana flows from this gap into neighboring states, undermining Plaintiff States' own marijuana bans, draining their treasuries, and placing stress on their criminal justice systems."

Nebraska and Oklahoma argued that Colorado's voter-approved system of taxed and regulated marijuana commerce conflicts with the Controlled Substances Act and thus violates the Constitution's supremacy clause.

They seek an injunction invalidating the sections of the Colorado legalization law that regulate legal marijuana commerce.

But in its brief urging the high court to dismiss the lawsuit, the Solicitor General argues that the Supreme Court is not the proper venue for the case because Nebraska and Oklahoma show no direct injury by the state of Colorado (as opposed to third parties acting criminally) and it is thus not a proper case of original jurisdiction.

The proper jurisdiction, the Solicitor General suggested, was federal district court.

The state of Colorado is fighting the lawsuit, and the Solicitor General's brief largely followed the arguments of the state in its briefs.

Drug reformers applauded the action.

"We are pleased the DOJ agrees that this lawsuit borders on the frivolous. States have historically been allowed to establish their own criminal laws," said Jolene Forman, staff attorney for the Drug Policy Alliance. "Moreover, Colorado is putting resources into ensuring its policies follow DOJ guidelines and has worked extensively with the DOJ towards this goal."

The federal government itself has not challenged the regulatory law in Colorado, nor did they choose to interfere with its implementation. To the contrary, the government has deprioritized enforcement of state-level marijuana reforms and acknowledged the interests that both states and the Federal government have in openly regulating marijuana.

"Nebraska and Oklahoma's primary problems are their own punitive policies regarding marijuana use and possession," said Art Way, Colorado State Director of the Drug Policy Alliance. "It is not Colorado's fault these states look to spend such a high degree of law enforcement and judicial resources on marijuana prohibition. Nebraska and Oklahoma should look to establish policies based on the potential harm of marijuana as opposed to simply using marijuana as the gateway to their criminal justice systems."

"This is the right move by the Obama administration," said Tom Angell, chairman of Marijuana Majority. "Colorado and a growing number of states have decided to move away from decades of failed prohibition laws, and so far things seem to be working out as planned. Legalization generates tax revenue, creates jobs and takes the market out of the hands of drug cartels and gangs. New federal data released this week shows that as more legalization laws come online, we're not seeing an increase in teen marijuana use, despite our opponents' scare tactics," he continued.