(CNSNews.com) - A watchdog group that monitors non-profit organizations has filed a complaint with the Internal Revenue Service, alleging that the environmental group Greenpeace is "knowingly and systematically violating U.S. tax laws." Public Interest Watch of Washington, D.C., formally filed the IRS complaint Monday, asking the federal agency to investigate Greenpeace's non-profit financial practices. "The most obvious, blatant violator of the non-profit [tax] law was Greenpeace. They are mooching off the taxpayer every year," said Mike Hardiman, executive director of Public Interest Watch (PIW). According to PIW's report, the tax-subsidized division of Greenpeace failed to follow federal non-profit tax guidelines...