With the coalition government declaring an end to chauffeur-driven ministerial cars, more and more politicians will be turning up on public transport. But how do you spot them? Here's a handy guide:
Watch for frustration at station barriers If you see a man trying to swipe his parliamentary pass over the Oyster card reader, chances are he's new to both government and public transport.
Is the suspect carrying a red box? Ministers who travel on trains are already given less noticeable black briefcases and it is presumed this practice will be extended to those on the No 23 to Parliament Square. See if they ask the bus driver to drop them off round the back.
Look out the back window Is there a black Jag full of ministerial paperwork following your bus?
Assess platform behaviour Ministers will instinctively gather at the far end of the tube platform, because they believe that's where the first-class carriage will stop.
Listen to their phone conversations Are they being interviewed by the Today programme? Tory ministers are likely to be heard describing their journey to a disbelieving friend: "It's a sort of train, but it travels through a long hole in the earth." They won't be talking to anyone because you can't get a signal on the tube, but they won't know that.
