What happens if a speed camera flashes two cars at once in France?

Reader Question: A speed camera flashed my car while I was driving, but it was on a motorway and there was another car driving next to me at the same time. Does this mean I won’t get fined? 

The stereotype that a speed camera flashing multiple vehicles is unable to issue fines is only partially true, and is indeed becoming rarer as technology advances. 

It is true that readings from certain speed cameras cannot be used to penalise or fine a driver, if there are multiple vehicles in the photos taken. 

A June 2009 decree states that: “when two or more vehicles of different speeds enter the measurement beam simultaneously, the device must not give any measurement result.”

This means that in cases where a radar flashes two vehicles at the same time, this cannot be used as justification for a speeding ticket, as an official measurement cannot be made from it.

In the 15 years since this decree was passed, speed camera technology has progressed considerably. 

Newly-installed cameras classified as radars discriminants can distinguish between vehicle types and the lanes on the road they are covering. 

This means the 2009 decree does not apply to them, as the readings from the camera’s measurements apply individually to each lane.

There is no risk of the camera confusing the readings of two vehicles captured at the same time as long as they were driving on different lanes.

France’s Sécurité Routièrè website counts 536 such radars across the country’s multi-lane road network as of July 20, 2026, out of 3,562,

Note this number may not be accurate, and does not account for private radar vehicles that operate on roads, nor mobile radars that can move location. 

Check whether you want to contest fine

Remember, there are ‘margins of error’ for vehicles flashed speeding that rule out fines for those within certain thresholds. 

The exact margins depend on the road and camera that flashes the speeding vehicle – full rules can be found here.

If you are flashed, you can request the photos taken by the radar if you wish to contest the fine. 

This may help you establish if there was any interference when your vehicle was flashed, but if you were caught by a radar discriminant that distinguishes between lines then this is less likely. 

Read more about contesting a speeding fine in our article here. Paying the fine is an admission of guilt, so do not do this if you wish to contest it.