Rule 39 is taking another step.

The Iditarod Trail Committee Board of Directors have revised the rule putting more responsibility on a musher for a positive test for his or her dogs.

A case in last year's race prompted the amendment. Several dogs from one team tested positive for a banned substance. Neither the musher nor the substance was revealed by the ITC.

The difference between Rule 39 now vs. then, is how the rule was written. Before, the ITC would have to prove intent. Now, if a musher's dog tests positive, an explanation will be in order. A review from an independent board would have to determine that the musher was not at fault due to "causes completely beyond their control."

"We've had this drug testing policy in place for more than 20 years," said Chas St. George of the ITC. "It has improved every year. We've picked up traces before of prohibited substances in kibble."

But this time the numbers were too large to ignore.

"That's a big part of it," he said. "The multiple dogs and the amount. There's a life on every one of these drugs, so it was definitely different than traces."

Should a musher face a review board, a polygraph test could be utilized.

Positive tests of drug usage have become commonplace among high profile athletes. From cycling great Lance Armstrong to home run champion Barry Bonds, performing in their sport cleanly was surrounded by accusations and ultimately proof of cheating.

While the financial stakes may not be as high as the Tour de France or Major League Baseball, the Iditarod is moving in a direction of more accountability and transparency.

Read the official statement below.