This probably doesn't come as much of a surprise, intuitively, but now there's some research to back up that suspicion: Bloomberg News reports that several university studies that downplayed the risks of fracking were funded, at least in part, by the natural gas industry itself.
Some of the instances cited by Bloomberg include:A 2009 report on the effects of increasing taxes on fracking in Pennsylvania, which contributed to a proposed 5% tax being rejected by the state legislature. The report received $100,000 in funding from the Marcellus Shale Coalition, but failed to disclose the funding.
A study done at the University of Texas, Austin that found no evidence of fracking contaminating groundwater. The professor leading the research did not reveal that he was on the board of the natural gas company, and received $400,000 in compensation for his work there.
A report this May from SUNY Buffalo did not disclose "extensive ties" between its authors and the natural gas industry.
Much more detail at: Bloomberg News