If you spot a traffic officer at the side of the road with a speed camera you're likely to slow down instinctively, or at least check your speedometer.
Well, Cape Town Traffic Services is making use of this to try and cut down on speeding offences - the official you're braking for might turn out to be just a cut-out and not a real person at all.
It seems social media has just woken up to this tactic. The recent Facebook post by South Africa Live above, has been shared hundreds of times.
However, traffic spokesperson Richard Coleman tells 702's Clement Manyathela they've been making use of these mock-ups for almost two years. And, he says, they've received only positive feedback.
It has been effective because once a driver sees a speed camera or officer along the road it's natural for them to stop and of course quickly on the phone, let his buddy know there is a speed trap out there, so be careful.— Richard Coleman, Traffic services spokesperson - City of Cape Town
Coleman emphasizes this is just an addition to the normal enforcement duties carried out by flesh-and-blood officers.
This is just where we have the very high accident rate, just to cover the areas most of the days we'll put out one or two of these. At this stage we've got four of them.— Richard Coleman, Traffic services spokesperson - City of Cape Town
For more on the City's strategy to "con" drivers into slowing down, take a listen: