Part of the reason for this trend stems from recent laws that restrict the amount of pseudo-ephedrine, a key ingredient in meth manufacturing, that an individual can purchase at one time.
The effect has been that it is more difficult for people to get the ingredients to make meth at home or in their vehicles: "We've seen a decline in homemade meth because of this law."
A mobile methamphetamine lab was found in the vehicle of one of the men arrested. Rawson said that some highly addicted people will get around the new laws by doing something they called "smurfing," where they go from one drug store to another and buy the maximum legal amount of pseudo-ephedrine off the shelf in order to have enough of the ingredient to "cook" the drug.
Though the new laws have helped to reduce the number of new meth users, they don't necessarily translate into a smaller quantity of the drug overall in the United States.
Rawson says that Mexican cartels have moved in to supply the meth markets that are already well established.
The result, he said, is higher priced meth that is more potent and more addictive.