Some U.S. Postal Service locations failed to properly handle ballots during this year's primary elections, a new audit from the agency's Office of Inspector General finds. 

The Sept. 4 audit attributed the mishandling to a lack of training for postal staff on how to quickly and properly handle mail ballots, deficiencies in how the ballots were tracked and errors that caused delays, Propublica reported. 

All these shortcomings, the audit found, risked ballots being incorrectly postmarked or otherwise arriving late to election officials, which would have resulted in the ballots being rejected. 

The findings come as the Supreme Court considers whether to allow the Postal Service to follow new rules set forth in President Donald Trump's executive order that requires states to provide the USPS with their voter rolls so the USPS can verify if the ballots are being sent to those who are eligible to vote.