The Defense Department spent nearly $1 billion on improper travel payments to military personnel and DoD civilians between 2016 and 2018, according to a report published last week by the Government Accountability Office.
Over the course of three years, the Pentagon paid out $18.3 billion in reimbursements for official travel through the Defense Travel System. But of that, $965.5 million -- more than 5 percent -- were improper payments.
An improper distribution means the amount distributed was either more than the correct payment, or should not have been processed.
GAO officials stressed that an improper payment doesn't necessarily represent a monetary loss to the government, as the total includes legitimate payments that initially lacked supporting documentation.
But the watchdog agency noted that in fiscal 2017 and fiscal 2018 -- the first years DoD tracked the government's monetary loss from improper payments -- about $205 million, or 37%, of $549 million in improper payments were lost.
Improper travel payments have long been a significant problem; they totaled $151 billion for the entire federal government in fiscal 2018.
To address the issues and prevent monetary loss, the Pentagon is required to estimate the amount of improper payments made in programs susceptible to overpayments or mistakes, and to implement corrective actions.
But the GAO found that the DoD travel pay system has not met those requirements for at least seven years.
"Since 2012, the Department of Defense Inspector General has consistently reported that the department has not met [its] requirements," GAO officials wrote.
According to GAO, DoD failed to publish valid estimates of improper payments, and its actions to reduce improper travel payments were inadequate. Corrective actions taken by DoD to fix the problem did not include identifying the reasons the payments were made in the first place, the report found.
"GAO found that these efforts did not clearly identify the root causes of the errors, in part because there is no common understanding of what constitutes the root cause of improper travel payments," they wrote.
DoD travel reimbursements grew more than 16% from 2016 to 2018, from nearly $5.7 billion to $6.63 billion.
Most of the travel reimbursements -- 52% -- went to active-duty personnel. The largest category of payments, 36% of the total, was for training-related travel.
"Other travel," defined as travel for "reasons not covered by other trip purpose categories," accounted for the next-largest amount, followed by "special mission" travel, which included travel for "non-combat military missions and travel to provide security for a person or shipment, among other missions."
The GAO made five recommendations to fix the issues, to include considering the data on improper payments in its remediation efforts, weighing cost effectiveness in deciding how to address improper payments and defining the term "root cause" so that everyone involved in addressing improper payments is on the same page.
DoD officials concurred with most of the GAO recommendations but took issue with several conclusions in the report on its remediation efforts and action plans.