Two cars collided on the A40 while trying to overtake a tractor on Wednesday morning.
Both a BMW i3 and a Ford KA were attempting to pass the tractor when they crashed, causing the BMW to flip over.
The driver, a woman in her 80s, suffered minor injuries but no one else was hurt in the incident between Sherborne and Northleach.
Police are appealing fort witnesses to the incident, which occurred at 10:30am, to come forward.
The Ford was white in colour and the BMW was black.
Information can be submitted by completing an online form and referencing incident 130 of June 23.
Alternatively you can call 101 with the same information.