Abu Dhabi Traffic Police

I followed a police car all the way across the Yas/Saadiyat 5 lane highway today. A few observations:-

• I drove all the way either in the inside lane, or next left if overtaking
• The police car drove all the way in the outside lane or next right
• The police car drove well above the speed limit for the whole journey and never changed speed for any section whether the limit is 100 or 80. Mostly they went at 130-140
• At this speed they allowed at least one car overtake with no action
• On the Sheikh Khalifa Bridge a truck had split a load of either flour/powder paint/cocaine across two lanes of the highway - police didn’t stop
• Also on the bridge a very large, fully loaded lorry was parked on the hard shoulder, wheels barely off the highway - police didn’t stop

What exactly do the traffic police do?