It's been a year since Colorado legalized recreational marijuana, and the state could not be happier with the results.  The move has reduced crime rates while growing its tax revenue base on the sale of the plant and its byproducts, according to a study published by a drug policy reform group.

"Given that arrests such as these cost roughly $300 to adjudicate, it is reasonable to infer that the state is saving millions in adjudicatory costs" for marijuana-related arrests and prosecutions, the study says.

Additionally, tax revenue from recreational marijuana sales brought in at least $40.9 million into the state's coffers.

"We've had great experience in Colorado and we hope the rest of the country can learn from that," Rep. Jared Polis, D-CO, said Tuesday during a teleconference. "I'm encouraged by the general direction."

The legalization didn't come without its share of controversy, however.  Lawmakers in Oklahoma, for example, filed a lawsuit against Colorado over the issue. Now, however, it seems many lawmakers have had a change of heart, and they are calling for the state Attorney General Scott Pruitt to drop the lawsuit saying that it's the "wrong way to deal with the issue."

The lawsuit, titled the States of Nebraska and Oklahoma v. State of Colorado, was filed in December contending that the newly legal marijuana from neighbor Colorado is being illegally trafficked across their borders.  They argue that under the U.S. Constitution's supremacy clause, Colorado's decision to legalize the drug cannot stand while it remains illegal under federal law.

Oklahoma lawmakers fear that a decision against Colorado could have broader implications than they originally hoped.

"If the federal government can force Colorado to criminalize marijuana," the letter reads, "using the exact same arguments, it could also force Oklahoma to criminalize a wide range of goods and activities that would be an anathema to the citizens of Oklahoma that we are sworn to serve."

Colorado Attorney General John Suthers has gone on record saying the suit is "without merit" and he will "vigorously" defend his states marijuana laws if necessary.

In the meantime, Colorado continues to enjoy the benefits of the law.  "The doomsday vision of those who support continued prohibition has not come to fruition," says Art Way, the DPA's Colorado director.

Since the law went into effect, Colorado has seen a 9.5 percent drop in burglaries in Denver and an 8.9 percent decline in overall property crime. Andrew Freeman, director of marijuana coordination for Colorado Gov. John Hickenlooper, said legalization had paid for itself, but was not an answer to all of the state's funding needs.

"There's been too much emphasis on money. It's not something that you do to fill budget shortfalls," Freeman says.

He said marijuana tax revenue had been able to pay for the costs of regulating the drug, and had funded programs intended to keep youth away from abusing substances such as alcohol and tobacco.