In conjunction with the April 15 tax deadline, the organization Americans for Tax Fairness released its annual report on Walmart and the Walton Family.

Subtitled "How Taxpayers Subsidize Americas's Biggest Employer and Richest Family," the report concludes the company and its founding family received $7.8 billion in tax breaks and taxpayer subsidies in 2013, featuring:

• $6.2 billion in public assistance to Walmart workers, namely Food Stamps and Medicaid

• $1 billion in federal tax breaks, notably via the use of accelerated depreciation

• $670 million directly to the Walton family due to lower tax rates on capital gains and dividends vs. wages

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Walmart (WMT) calls the report "inaccurate and misleading” and even some who support its overall focus take issue with the specific findings.

The $1 billion in federal tax breaks cited by Americans for Tax Fairness overstated the case by about $900 million, according to David Cay Johnston, a Pulitzer Prize winning reporter, author and professor at Syracuse University Law School. "They mis-measured it -- they took the current benefit instead of the time value benefit," he says. "It's a lot of nerdy stuff...but I think that $1 billion should be $100 million."

Another critique of the report is that the Walmart workers receiving federal benefits would be worse off without those jobs, potentially costing the U.S. government (and taxpayers) even more money. Furthermore, Jason Furman, chairman of the White House Council of Economic Advisors, recently wrote that the percentage of Walmart workers on Medicaid is in line with other major retailers. “The fact that Walmart employees top Medicaid rolls in a number of states is simply a reflection of Walmart’s enormous size, not the higher likelihood that its employees will be on Medicaid,” he writes.

On the issue of government assistance for Walmart workers, Johnston is in league with the Americans for Tax Fairness.

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People at Walmart can certainly say '[the payments are] not directly to us'. No it's not but it is subsidizing Walmart because it's their business strategy to hire people in a way that many people would need Food Stamps," he says.

Via email, a Walmart spokesman (naturally) responded with the company line: "Walmart provides associates with more opportunities for career growth and greater economic security for their families than other companies in America. Our full and part-time workers get bonuses for store performance, access to a 401K-retirement plan, education and health benefits."

But Johnston, whose books include The Fine Print: How Big Companies Use 'Plain English' to Rob You Blind and Free Lunch: How the Wealthiest Americans Enrich Themselves at Government Expense, is unmoved by this response.

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