As it does every year during filing season, the IRS released its annual list of the top 12 Dirty Dozen tax scams, updated for the 2017 filing season. Anyone following the news this year and last will not be surprised that the No. 1 scam was phishing, which has affected tax preparers, company payroll and human resources departments, and individual taxpayers. Second is phone scams, which involve fraudsters impersonating the IRS, calling and threatening people to get them to pay amounts they may not even owe, and often asking for untraceable forms of payment. Here is the IRS's list of this year's top dozen worst scams.