Mitt Romney can’t possibly think he can get away with this.

The multimillionaire former governor of Massachusetts and presumptive Republican presidential nominee has released two years of tax returns, from 2010 and 2011.

Last week, his spokesman said that would be all. “We think that’s sufficient,” Eric Fehrnstrom told NBC News.

Is he joking?

Presidential candidates need to release multiple years of returns; President Barack Obama released returns dating to 2000 during the 2008 campaign; George W. Bush made public his returns from 1991 forward. Even some of Romney’s Republican rivals have called on him to disclose more, predicting that his failure to do so will give the Democrats ammunition this fall.

Tax returns are one of the few ways voters can accurately assess candidates’ values — not just what they say they believe. They show what causes candidates support, how they’ve conducted their careers and where their wealth comes from. They also show whether candidates have now, or have had in the past, any conflicts of interest between their investments and their governing decisions.

In Romney’s case, the returns are especially important. Romney downplays his time in public office and says his experience as head of the private equity firm Bain Capital has prepared him to be commander in chief. His tax returns will give voters a fuller vision of how he performed in the role he says would make him a better president than Obama. As The Washington Post reported last week, other financial disclosure forms Romney must file allow him to legally hide an unusually large portion of his assets from public scrutiny. Tax returns will help fill out the picture.

The two returns Romney did release raised questions that only further scrutiny can answer. Because Romney earns his money through investments and not work, in 2010 and 2011 he and his wife paid a tax rate of about 15 percent on $45 million in income those two years — a lower rate than many in the middle class. Has he benefited from this rate in previous years? Just how little did he pay? What offshore investments has he previously held, and to what extent, if any, have they helped him avoid taxes?

Voters need to know more about how Romney’s low tax rate relates to the way he proposes to govern. No one begrudges Romney his wealth; he obviously worked hard during his years in business. But he must explain why he believes his and others’ phenomenal wealth — earned in part with the help of public infrastructure, such as roads, bridges and schools — should be further rewarded by a low tax rate that will reduce public investment in those basics.

Does he think federal tax policy has played a role in the widening gap between rich and poor? If not, what does he believe is the cause? Does he think the gap ought to be narrowed, say, back to the way it was in the Reagan era, and if so, does the federal government have a role to play?

In 2008, when John McCain was vetting potential running mates, Romney reportedly provided 23 years’ worth of returns.

Was there something in them that sent McCain fleeing to the other end of the continent and Sarah Palin?

Voters should get the same opportunity McCain had to examine Romney’s background.

Editorial by the San Jose Mercury News distributed by MCT Information Services

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