Matthew Alacon, 1, plays at the register as clerk Jessica Martinez, right, checks out Isabel Mendoza's groceries at a grocery store in Houston, Tuesday, May 1, 2007. On display in the foreground are bilingual supermarket shopping guides, Camino Magico, which feature a new food pyramid designed to encourage Latinos to make healthier food choices with traditional foods are on display. The pamphlet is the centerpiece of a nationwide campaign to improve eating habits and reduce obesity and diabetes among Latinos. Pat Sullivan/AP Photo

Chad Stone is chief economist at the Center on Budget and Policy Priorities.

The House and Senate agriculture committees are holding hearings this week on reauthorizing SNAP (the Supplemental Nutrition Assistance Program, formerly known as Food Stamps). We'll hear claims from some quarters that "waste, fraud, and abuse" and "explosive" growth in enrollment and benefit costs have produced a program bloated well beyond what's needed to serve the truly needy.

Don't believe it; SNAP is doing what it's supposed to do, and the Congressional Budget Office projects that SNAP spending will grow more slowly than the economy in coming years.

My colleagues at the Center on Budget and Policy Priorities, who are among the country's foremost SNAP experts, have laid out the facts here and here.

Let's start with claims about out-of-control costs. As the chart below shows, SNAP costs did rise substantially between 2007 and 2011. The reason, however, is overwhelmingly economic. By design, SNAP provides modest benefits to eligible vulnerable people, and the number of such people rises when the economy weakens. CBO found that about two-thirds of the increase in spending on benefits between 2007 and 2011 reflects higher program participation due to the economy:

The primary reason for the increase in the number of [SNAP] participants was the deep recession from December 2007 to June 2009 and the subsequent slow recovery; there were no significant legislative expansions of eligibility for the program during that time.

Another 20 percent of the increase in costs reflects a temporary increase in SNAP benefits – which President Obama and Congress enacted as part of the 2009 Recovery Act – that ends later this year. The remainder reflects other factors that automatically boost benefits, such as higher food prices and lower incomes among recipients due to the weaker economy.

CBO projects that an improving economy will reduce the share of the population that participates in SNAP to its 2008 level in coming years; accordingly, costs will fall as a share of the economy. That's because most SNAP beneficiaries who can work want to and do work when jobs are available. About two-thirds of SNAP recipients aren't expected to work, mostly because they are children, elderly or disabled.

But, as the chart below shows, work rates are high among SNAP households with at least one working-age, non-disabled adult while they receive SNAP – and higher still within a year before or after they receive SNAP.

Conservative critics of SNAP and other federal social programs like to portray them as turning the United States into an "entitlement society" by undermining the work ethic and creating a class of people dependent on government programs. That's not true of SNAP and it's not true of other federal health and income security programs. CBPP analysis finds that more than 90 percent of the benefit dollars that these programs spend go to assist people who are elderly, seriously disabled or members of working households – not to able-bodied, working-age Americans who choose not to work.

The "entitlement society" myth is often paired with similarly discredited arguments that SNAP and other federal social programs are poorly run or have high administrative costs. In fact, SNAP has a strong record of efficiency. It has one of the most rigorous quality control systems of any public benefit program. SNAP error rates (benefit overpayments and underpayments) are at an all-time low; just 3 percent of benefits went to ineligible households or exceeded the allowable benefit for eligible households. Moreover, honest mistakes by recipients, eligibility workers, data entry clerks or computer programmers – not fraud – account for an overwhelming majority of such overpayments.

Conservative critics who want to cut SNAP sharply or radically restructure the program say such "reforms" are necessary because the number of people claiming benefits and benefit costs are spinning out of control, the program is discouraging work and creating dependency, and it's rife with waste, fraud, and abuse.

The facts, however, say otherwise.

Read Kenneth Thomas: Reducing Unemployment Is More Important Than Reducing the Budget Deficit

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