At 33 sites across the country, IRS auditors had their nametags and their best behavior on display as they sacrificed part of their weekend to help the taxpayers.
The test uses a chemical called florbetapir, known by the brand name Amyvid, which is a radioactive agent that tags clumps of a sticky substance called an amyloid.
The identification of more than 10, 000 participants by name was completed by tagging individuals in Facebook, breaking a record for the number of tags in a given image to date.