How many federal employees are members of a union? The correct number should be easily found on the Internet, but the amount of information available can often make getting the right statistic confusing. Take, for example, the following passage from a recent editorial by Economics 21, which read:

 “According to BLS, 7.9 million public sector workers belong to unions, more than the 7.4 million private sector unionized workers. Of these 7.9 million unionized public employees, less than 2.75 million are federal [source in original] workers. The remaining 5.1 million – nearly two-thirds of the total – are state and local employees. As a consequence, if escalating compensation costs are a main driver of government spending, one would anticipate seeing larger increases at the state and local level.”

   Would that paragraph lead you to believe that there are 2.75 million federal union members (100% of the federal workforce) or 1,005,000 (about 37% of federal employees)? The true answer, as the Bureau of Labor Statistics helpfully illustrates is the latter, smaller number. The respective numbers are 4.867 million local employees and 2.025 million state employees, comprising 87% of public sector workers.

   I do not make this point to single out this one article. After all, every researcher makes mistakes now and then. And this passage is what Dan Rather might call “inaccurate, but true” - the correction makes the argument even stronger - the true costs of public employees unions are overwhelmingly at the state and local level. But bad statistics have a way of begetting bad policy: a common example is the ham-fisted comparison of average salaries which is somehow rhetorically twisted into alleged proof of disequilibrium in the labor market.

   In the above example the breakdown between private and public sector union membership comes from the BLS, but the number of federal workers comes from a different source which is addressing a different question entirely. Their proximity in the writing leads to the implied transfer of statistical authority and the ensuing confusion.

   The larger point is the danger that the easy authority of statistics allows, especially as the public becomes engaged in the heavily numerical discussions of debt, taxes, and spending.

   Mark Twain famously said that there are “lies, damn lies, and statistics.” Citizens who wish to be informed will have to check and double-check many of the numbers likely to be thrown around in the future and, as always, consider the agenda of the source, especially when it’s an agenda with which one might agree. We are more likely to believe numbers when they confirm what we think we know.

   And because statistics make easy slogans for politicians they will have to be checked regularly, and their staff should be sure to get the numbers right. When they do not, they should be held to account, as strongly as for any easily made and quickly discarded campaign promise. Because when politicians move on from lies and damn lies, they are not just betraying themselves, but our trust and intelligence.