The government shutdown left the IRS with over 5 million pieces of unsorted mail.
That's just one of the effects of the shutdown the National Taxpayer Advocate (NTA) discussed in its annual report to Congress.
The NTA, an internal IRS organization, delivered its report to lawmakers Tuesday.
The NTA asserts that it's "irresponsible for an agency that touches all aspects of people's lives to be underfunded, understaffed, and at the mercy of shutdowns." The government shutdown happened right before tax season started, leaving the IRS without a full staff at one of the most crucial times. For the first part of the shutdown, IRS employees weren't allowed to perform many basic functions like answering phones or issuing refunds.
Even when employees were told to return to work, they were unpaid, and many didn't show up. When the shutdown ended after 35 days, the IRS had a backlog of items to process. The NTA suggests the law responsible for government shutdowns is outdated and should be amended to allow the IRS to be properly staffed when the government is closed.
It also said the IRS' biggest problem is outdated technology, and that funding to replace its core tech would improve service overall. The next deadline to fund the government is Friday, and according to Bloomberg, a second shutdown could cause more problems for tax season, including refund delays. Additional reporting from Newsy affiliate CNN .