(CNN) A bipartisan group of lawmakers introduced legislation on Thursday to fix a change in President Donald Trump's tax law that unexpectedly stuck some families of fallen service members with higher tax bills this year.

Survivor benefits designated to children were previously taxed at the parent's rate, but changes in the 2017 tax law , which Republicans say were intended to simplify tax rules for child income, led to the steep hikes for some Gold Star families. The government instead began treating the Defense Department benefit as if it were a trust or estate, meaning it could be taxed at rates as high as 37%.

The change, first reported by the military website Task & Purpose, has drawn outrage from members of Congress. Minnesota Democratic Sen. Amy Klobuchar, a presidential candidate, called on the Treasury Department to address the problem.

The new bill, titled the Gold Star Family Tax Relief Act, would clarify how income from the Department of Defense's Survivor Benefits Plan should be taxed. It would also be retroactive, meaning it would cancel out the hefty tax increases that some families experienced for 2018.

Virginia Democratic Rep. Elaine Luria, a retired naval commander, is leading the effort. She has support from seven Democrats and eight Republicans who have signed on to the bill.

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