In a heavily redacted report obtained by The Kansas City Star through a Freedom of Information Act request, the Treasury Department's inspector general for tax administration said the city failed to follow "proper safeguards for protecting federal tax return information."
The tapes were delivered to City Hall in August 2006 to help revenue officials make sure people living or working in Kansas City are paying the 1 percent city earnings tax.
City officials said they realized the tapes were missing in late 2006, touching off the investigation that began on Dec. 19, 2006, and lasted until Nov. 1, 2007. The tapes have never been found.
"The investigation revealed the city did not follow and was not following the proper safeguards for protecting federal tax return information," the inspectors wrote.
The information released to The Star and published in a story Saturday did not elaborate on the city's mistakes. Most of the information in the 42 pages provided to the paper was blacked out, and the agency said it wasn't handing over another 105 pages because that "could impede its law enforcement activities."