SAN FRANCISCO (KCBS) – With the arrest of state Senator Leland Yee this week on corruption and gun trafficking charges, the website MapLight has been following the money trail, in terms of his political campaigns.

Daniel Newman, president and co-founder of MapLight, said they have been pouring over records that show just how the state senator went about financing his various campaigns.

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“We went several years back, and certainly, some of the people mentioned in the allegations against Senator Yee have been giving campaign contributions. But overall, his campaign contribution pattern is similar to many other legislators,” Newman said. “For example, unions are one of his top contributors, and he also received money from Time Warner, and other companies too.”

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Newman said with the numbers, he found it interesting to look at the scandal of what is legal, compared to what is alleged illegal. For example, Yee is alleged to have received campaign contributions, and then wrote a letter to the State Department of Health to try to exercise influence on behalf of that contributor. Newman said this happens all the time, it was just that Senator Yee was caught by the FBI saying he was doing this because of the money.

Newman said perhaps a bigger issue is the system where politicians need big campaign money to get elected.

“We have current lawmakers in Sacramento saying essentially, this is just a few bad apples. But really, it’s our broken money and political system that elects lawmakers who trade off money for influence,” he said.

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Click here for a closer look at the research into state Senator Leland Yee’s campaign contributions.