Since leaving front-line politics, David Miliband has resisted the urge to air his views in public.
The same can't be said for his crotch.
The former Shadow Foreign Secretary, 47, failed to mind the gap on a Piccadilly line tube while taking a mid-afternoon nap.
Electrician Francis Janjua got on the London Underground at Leicester Square and sat opposite the MP for South Shields, who was reading a book.
But minutes later the former Labour leadership contender nodded off with his trouser fly gaping open.
Francis, 28, said: "Pretty much as soon as the tube set off, he closed his book and put his head on his hand and dozed off.
"He was properly asleep, I reckon.
"I was laughing to myself about it anyway, until I noticed his fly was down - then it was just hilarious."
Miliband fell asleep in a priority seat designated for disabled people and those less able to stand, although the Tube was not busy at the time, around 3pm on January 16.
He dozed for around 20 minutes until the train stopped at South Kensington, where he disembarked - without noticing his zipper was undone.
Francis, who was travelling to his West London home from a job, said: "I couldn't believe his fly was down.
"It kind of takes the credibility away from him a little bit. But he's still got more credibility than his brother."