Massachusetts Sen. Elizabeth Warren, the populist Democrat and foe of big banks, has not listed a $1.3 million credit line against her home with Bank of America on annual financial disclosure documents because of a loophole in federal law, according to a new report.

The Boston Herald reported Wednesday that Warren, who is required to disclose financial assets and liabilities, avoided listing it in 2014 because it’s a line of credit — not a mortgage — and the Democrat doesn’t actually owe enough money yet.

Here’s how the Democrat’s office explained the situation to the Boston Herald: “An aide for Warren said the amount represents a home equity line of credit, not a mortgage. According to the aide, a line of credit does not trigger reporting requirements if the borrower has not borrowed on it, or if the amount owed is less than $10,000. Warren’s account had a zero balance, the aide said.”

Referencing the 2012 STOCK Act, the paper also noted that “a loophole — the act’s failure to mention lines of credit — let Warren keep her interest rate and other information about the home equity line private.”

As expected, Republican critics are pouncing on Warren.

“Splitting hairs between a ‘line of credit’ and a ‘mortgage’ to try and explain away potential violations of federal disclosure laws is a very 1 percent kind of problem to have, particularly when the loan is question is to the tune of 1.3 million dollars,” said Colin Reed of the Republican opposition research outfit America Rising.

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