Electoral-vote.com gives us this concise summary of Troopergate:
If you haven’t been following the story, known as Troopergate, here is an executive summary. Palin’s sister, Molly, was involved in a bitter divorce and child custody fight with her former husband, state trooper Mike Wooten. Palin, who supports family values, wanted to help her sister in the custody battle by causing her ex brother-in-law to be unemployed. So she asked the state commissioner of public safety, Walt Monegan, to fire Wooten. Monegan refused. Wooten had been involved in some misconduct earlier, but Monegan told Palin that Wooten had been disciplined for it already and the case was closed. Monegan further told Palin to get off Wooten’s case because that might be seen as an ethics violation. Palin took his advice and assigned her husband, Todd Palin, the job of getting state employees to work on getting Wooten fired. One of the attempts was a telephone call that was (lawfully) recorded and later released. Branchflower found over a dozen specific incidents where state employees took action to try to get Wooten fired. Ultimately, Palin got frustrated with the process and fired Monegan. This firing was what started the investigation.
Palin denies all wrongdoing and says the report is politically motivated. However, the investigation was started before Palin was chosen to be the vice-presidential nominee, the Republicans control the state legislature, and the report was released yesterday by a unanimous vote of the bipartisan Joint Legislative Council, which had oversight on the investigation. The investigator, Steve Branchflower, is a retired prosecutor with a reputation for integrity. None of these facts suggest a political hatchet job. In fact, the president of the Alaska state senate, Lyda Green, a Republican from Palin’s home town of Wasilla, said: “The problem with power is that people pay attention to it. And it’s very easy to get beside yourself and use it in the wrong way. And we do have to leave personal business at home.” (source)
