ANCHORAGE, Alaska >> Iditarod officials have cleared a four-time champion of any wrongdoing in a dog-doping scandal that followed the sled dog race last year.

Officials for the 1,000-mile Iditarod Trail Sled Dog Race issued a statement this week absolving musher Dallas Seavey of any involvement in the drugging of his dogs, the Anchorage Daily News reported.

Four of Seavey’s dogs tested positive for tramadol, an opioid painkiller and banned substance, following his second-place finish in March 2017. Some Alaska veterinarians have questioned why anyone would administer the drug during the race because it may cause drowsiness.

Jeanne Olson, an Alaska veterinarian who treats sled dogs, sees no benefit in administering tramadol during a race because it causes drowsiness. Olson, who was the head veterinarian in the Yukon Quest International Sled Dog Race in the 1990s, prescribes it mostly for profound pain relief.

“But I also caution that the dogs are going to become sedated from it,” she said. “So when I first heard … that it was tramadol as the drug, I thought, ‘Well, that’s surprising. Why would anybody use that?’ “

“We met with him multiple times and there was (sufficient) evidence to conclude he didn’t have anything to do with it,” said Mike Mills, president of Iditarod’s board of directors.

Mills declined to say what that evidence was.

“It’s a hard situation to untangle, but we’re comfortable that we made the right decision,” Mills said.

Seavey said he presented a “very compelling case” to the race board. After the test results were made public last year, he had suggested that someone sabotaged his team.

“I can’t prove what did happen, but we can strongly prove what didn’t happen,” Seavey said.

Seavey said he can’t share of all the information about the case, but he noted that one of his arguments dealt with the timing of the drug tests. The dogs had high levels of the drug immediately before test, which he knew was coming.

“It does not look like something someone was trying to get away with. It’s very blatant,” Seavey said.

While Mills said Seavey did not have knowledge of the doping, officials have not determined who was responsible for it.

“We’re convinced we’re never going to figure that out,” Mills said.

Seavey raced in Norway instead of running the Iditarod this year. He hasn’t decided where he will race next year.

“I’m not entirely sure which way we’re going, but I’m training dogs,” Seavey said. “This whole situation over a whole year-and-a-half has been tiresome, to say the least. I’m focused on having fun with the dog team. The simple side of it.”