This year many Americans who are accustomed to receiving an income tax refund have found to their surprise that they actually owe money to the IRS.

Many of these tax payers filed early, when the paperwork becomes available. A tweet rounding up other tweets from January of displeased early filers went viral because the user, @smarxist, deliberately singled out people who are mad at President Donald Trump for raising their taxes.

inject this shit directly into my fucking veins pic.twitter.com/XIH43gzZHq — Direct Action Bronson (@smarxist_) February 4, 2019

The truth is somewhat more complicated.

The new tax law does result in some people paying higher taxes (especially over the long term), but the specific issue here is tax refunds rather than total taxes paid. Whether you get a refund or owe extra to the IRS at filing time is a function not just of your total taxes owed, but also of how much tax is withheld from your paycheck by your employer on paydays. And the big story here is that as a result of the new tax law, the Treasury Department tweaked things so that on average taxpayers’ withholdings fell by more than their actual taxes owed.

This was all explained in a Government Accountability Office report last summer, but it turns out that many people are not regular readers of GAO reports and did not take the GAO’s official advice to check their withholding status. The result? Surprise tax bills!

Tax withholding, explained

Income and payroll taxes are, in a theoretical sense, collected once a year in mid-April.

In practice, however, the government has employers calculate how much tax their workers are likely to owe at the end of the year. Then each pay period, companies simply forward an appropriate amount of money directly to the IRS and pay you what’s left over. When you file your taxes at the beginning of the year, you compare the amount of taxes you owe to the amount of taxes you’ve already paid and get either a refund or a request to send more money. And historically, by design, most people — around 75 percent — get a refund.

That’s because it’s a lot easier for the government to pay out refunds to people who overwithheld than to run around trying to collect cash from people who underwithheld.

What’s more, when underwithholding does happen, it’s usually either because of an error or else a special situation like a person with a full-time job who also happened upon an unexpected bounty of freelance side-gigs. In fact the government hates underwithholding so much that if you primarily derive your income from freelance or self-employment work, they start charging you a financial penalty unless you pre-pay your taxes on a quarterly basis.

This system was, in a fun historical irony, devised in part by Milton Friedman, the famous libertarian economist, who at the time was trying to help win World War II but who wound up being an unsung hero of the post-war welfare state. And the whole thing had been chugging along pretty peacefully until then-House Speaker Paul Ryan, Treasury Secretary Steve Mnuchin, and Trump decided to shake things up.

How the tax law changed withholding

The 2017 Tax Cuts and Jobs Act was largely focused on reducing taxes for rich business owners. People who are stand to inherit multi-million dollar estates got an enormous tax cut, as did people who own “small” businesses that generate millions of dollars in annual profits. And, of course, there was a big cut in the corporate income tax rate, with benefits largely flowing through to stock owners in a country where 80 percent of the value of the stock market is owned by the richest 10 percent of the population.

But there were changes for middle-class workers, too.

Most famously, TCJA either eliminated or curbed a whole bunch of popular tax deductions (including the home mortgage interest deduction and the state and local tax deduction) while also repealing a previously implemented phase-out of itemized deductions. Consequently, the value of most people’s tax deductions went down but some people got to deduct more. Then to compensate for these lost tax deductions, the Child Tax Credit got more generous and was also given to richer people and the standard deduction got much bigger. Individual tax rates, in turn, went down.

In the aggregate, this means higher taxes for a few people but lower taxes for the vast majority of Americans. It also means that virtually everyone’s tax situation is a little bit different from before, often in complicated ways related to the ins and outs of lost and gained deductions and credits. So everyone’s withholdings had to be calculated anew.

The bill was also extremely unpopular. But Republicans spent December 2017 assuring themselves that would change in February 2018 when the new withholdings began.

“On January 1, Americans are going to wake up with a new tax code,” Ryan said. “On February 1, they are going to see withholdings go down, so they are going to see bigger paychecks.”

Trump tweeted something similar.

.@POTUS: If Congress sends me a bill before Christmas, Americans will see lower taxes beginning in February. Just two short months from now. pic.twitter.com/XMuZfJL1dC — FOX Business (@FoxBusiness) December 13, 2017

This immediately lead the eagle-eyed David Dayen at the Nation to wonder whether Trump was planning to have his acting IRS commissioner (a political person rather than a tax enforcement professional, in an unusual choice to run the agency) deliberately reduce the withholdings to exaggerate the impact of the tax cut on people’s pocketbooks in advance of the midterms.

Since his article 14 months ago, no clear evidence of political manipulation has emerged. But the July GAO report confirmed that this is indeed what happened — both taxes owed and withholdings went down, but withholdings went down too much.

Treasury says the new system is more accurate

According to the GAO’s estimates, the number of people whose withholdings are exactly right will stay roughly the same under the new system.

The change is that fewer taxpayers should be overwithholding and more should be under withholding — in other words, fewer people will get a refund and more people will be asked to pay up.

Treasury’s viewpoint is that this is change for the better. Under the old system, 75 percent of taxpayers were getting refunds — meaning that the withholding system was poorly targeted on average. By switching to a new system in which fewer people get refunds and more people owe extra money, they will be achieving a more balanced result.

If this was intended to give Republicans a boost in the midterms it obviously didn’t work, in part because the once-a-year tax filing process is a lot more salient than the biweekly process of automatic withholding. In fact, they are now facing a backlash from an angry public that includes millions of people who were expecting tax refunds that they are now not going to get.

It’s actually the case that in the long run TCJA will raise many working- and middle-class people’s taxes. To conform to budget reconciliation rules, Republicans made it so the nonregressive tax cuts largely expire after 10 years while the revenue-raisers and the business tax cuts are permanent. But while this is an important (and telling) part of the tax policy debate, it doesn’t represent anything that’s happening this winter. People hit with a surprise request to pay extra to the IRS may feel like Trump surprisingly raised their taxes, but in most cases that’s not what’s happening.

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