Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
The independent complaints directorate says it has powers to initiate an investigation without a complaint.
And it's doing just that in the case involving the presidential VIP protection unit and a motorist who was allegedly shot at after he failed to give way to the flashing blue lights at the weekend.
Members of the VIP protection unit were escorting President Kgalema Motlanthe on the N12 when an allegedly drunk and defiant motorist drove close to the convoy and collided with one of the vehicles.
"We will interview the motorist and members of the protection unit," ICD spokesman Tommy Tshabalala said. "We have information that a shot was fired. We cannot ignore the incident since it was in the media.
"Remember that we have powers to initiate an investigation without somebody lodging a complaint with us. We are investigating allegations of misconduct or criminality."
Members of the unit allegedly confiscated footage captured by SABC journalists who were on the scene. Tshabalala said the investigation would be concluded within two weeks' time.
Police spokesman Sally de Beer said an investigation was under way with a view to instituting criminal charges against the driver of the red car and finding out if police acted within their mandate.