Why is the U.S. Coast Guard investigating these cases?

Two petty officers from USCGC Liberty are under Coast Guard investigation following state charges that they failed to salvage game meat as required by Alaska law. They had illegally dumped a deer and four ducks. According to this article:

Alaska Department of Fish and Game hunting regulations and state statutes requires that all edible game meat be salvaged and taken to a place to be processed for human consumption. Failure to salvage game meat is a class ‘A’ misdemeanor which can be punishable by up to a year in jail and a $10,000 fine.

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The Coast Guard is investigating the incident to determine whether disciplinary action should be taken against the two men, Coast Guard District 17 spokesman Chief Petty Officer Kip Wadlow said. Any action will be taken after the criminal court case is complete, he said.

“That can depend on the investigation,” he said, describing the range of possible repercussions by the military. “It could be anything just from administrative discipline to potentially something more severe under the (Uniform Code of Military Justice), depending on what the results of the investigation are.”

The Coast Guard is also investigating an officer who was cited by the state for illegally shooting a bear that was rummaging in trash in his yard.

Editor's query: Why can't the service leave these matters to local law enforcement? Ditto for this Coast Guard case of assault on civilians and being drunk and disorderly outside a bar in Key West? There the accused, who was acquitted of abusive sexual conduct, was sentenced to 30 days restriction and hard labor without confinement. Would a civilian court have been more lenient? Does it matter?