In 2007, 2012, 2013 and 2014, the Donald J. Trump Foundation stated that none of its money had been used to benefit Trump or his businesses. But the New York attorney general found that, in each of those years, Trump had used his charity’s funds to help one of his businesses. In 2013, the attorney general alleged, Trump also failed to disclose an improper gift to a political group.

In the suit, Underwood also accuses Trump of turning his charity into a tool of his 2016 presidential campaign, despite prohibitions on political activity by nonprofit entities. She also laid out her findings in a letter to the IRS, suggesting that federal authorities investigate further.

It is a felony to knowingly file a false tax return, with potential penalties of up to $100,000 in fines and up to three years in prison. In rare cases — where prosecutors could prove the falsehood to be deliberate — people have been convicted of signing false tax returns.