It's like a bad joke. Why did the Greek government borrow so much money?
Because it couldn't get its own citizens to pay taxes.
The Greek government estimates that one third of taxes owed never get paid. And apparently it was far easier to borrow money even at outrageous rates than to make Greeks pay what they owe.
So in 2009, the Greek finance ministry called in an unlikely hero: A methodical, computer science professor at Athens University, Diomidis Spinellis.
Spinellis tackled the problems like it was programming challenge. He made something called a mind map. A mind map looks like a tree, and it maps how your brain works. And Spinellis's mind map illustrated in a precise, clean manner why Greece is missing so much of its tax revenue.
First on the mind map. Locate the tax evaders, he thought, and improve tax collection. It should be easy, because wherever he looked in the data, he saw tax evasion.
For instance, a corporation often lists its shareholders and their compensation. Those shareholders also reported their income for their taxes. So he used a computer program to check that the numbers matched — the reported income should not be less than the compensation. But, Spinellis's program found in many cases, it was:
What we found is that some failed to declare that amount completely and others missed a digit so they declared ten times less what they actually had to declare.
Spinellis's program found hundreds of thousands of cases of potential tax fraud.
Greece has three hundred regional tax offices. Spinellis thought the solution was simple. Share the data with all of them and wait for the revenues to come flowing in.
Most Greeks will tell you there is widespread corruption in the tax offices. Collectors take bribes.
So Spinellis added a new item to the mind map. Management issues at regional tax offices.
Spinellis wrote a small program that would extract each day's performance data from every single tax office. It recorded information on how much revenue was collected, how many cases were closed, the number of days it took to close a case, etc. It also kept a list of the tax offices that had not closed a single case that day. There were hundreds of them.
The program sent an email every single afternoon to the finance minister and every tax collection office, reporting which offices did absolutely nothing that day. And still, days passed with no action.
It is around this point, two years in, that Spinellis had a disturbing thought. A new item on his mind map. Fixing Greece's tax system, and ultimately making the Greek economy work, was not a matter of tweaking his computer programs. It was not an information problem. It was a culture problem.
If the people don't want to pay taxes, the collectors don't want to collect, and the politicians don't want to punish them, perhaps Greece needs more than a mind map.
At the end of 2011, Spinellis resigned from his government job. He's back to teaching.
And for now, Greece is surviving on international bailouts from countries where people do pay their taxes. In just a few weeks European inspectors will travel to Athens to check if, among other things, Greece has increased tax collection. If the culture has finally changed.