An investigation out Sunday from Mike Elk at In These Times reveals how brothers David H. Koch and Charles G. Koch, the Koch Industries owners, are taking full advantage of the Citizens United ruling in attempting to control their workers’ votes.

The findings highlight a lesser talked about effect of the 2010 Citizens United ruling. "The Supreme Court decision overturned previous FEC laws prohibiting employers from expressing electoral opinions directly to their employees," Elk writes.

Elk found that the conservative duo sent a mailing to 45,000 employees at Koch Industries subsidiary Georgia Pacific this month. In the mailing, President and Chief Operating Officer Dave Robertson wrote a thinly veiled threat that "many of our more than 50,000 employees" may "suffer the consequences" if the wrong president is elected. The mailing also included an anti-Obama editorial by Charles Koch, a pro-Romney editorial by David Koch, and a list of Koch-endorsed candidates.

The company further exercised its control this, Elk found, by implementing a new social media policy in which employees cannot post anything that might go against the Georgia Pacific "brand" or reputation.

“Even if I was at my own home, I can’t put something up [on Facebook] against the Koch Brothers,” AWWPW Local 5 President Jim Pierce, who works at Georgia Pacific paper mill, in Camas, Washington, told In These Times. “I don’t post anything about the Koch Brothers. I could lose my job.”

Read the full story here.

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Up With Chris Hayes on Sunday morning detailed the investigation on the Koch brothers and similar behaviors by other companies:

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