'Judge flashed at me twice in eight days on rush-hour train'

The woman claimed Lord Justice Richards, 56, boxed her into a corner on the packed commuter service before the incidents took place.

She said that on the first occasion she assumed he must have left his flies open by mistake because he looked like a "very kind man".

But when it happened again days later, she reported the incidents to British Transport Police, and turned detective by taking pictures of the man on her mobile phone and trying to follow him.

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The woman, who is in her 20s but cannot be named for legal reasons, later identified the man during an undercover police operation as the Right Honourable Sir Stephen Richards.

But Richards, a married fatherof-three who sits in the Court of Appeal, told officers it must be a case of "mistaken identity" and insisted it was "not conduct he would engage in" as a member of society or of the judiciary.

Yesterday, Richards, of Wimbledon, appeared at the City of Westminster Magistrates' Court to deny two charges of indecent exposure.

He arrived holding hands with his wife Lucy.

The first incident is alleged to have happened on October 16 last year as the woman was travelling from Raynes Park, South West London, to Waterloo.

She claimed Richards, who was wearing a three-quarter-length trench coat, got on at Wimbledon.

"A gentleman was standing quite close to me but that could have been because it was quite busy," she said.

"I was standing near the door with my back to a glass panel and he was at right angles to me, boxing me in.

"I was just reading my newspaper when I noticed that he had exposed his genitals. I didn't really want to look too much because I was quite embarrassed, but I recall it was just the flies that were undone, not the buckle or the belt.

"His genitals were out of his trousers. I couldn't see any undergarments.

"He was very well dressed, very presentable, and looked like a very kind man which was why I thought this was an accident.

"Because I was embarrassed and nothing like this had happened to me before, I just assumed this was an accident so I didn't want to draw attention to this incident and potentially embarrass this gentleman as well."

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She did not report the incident, but told the court the same thing happened just over a week later on October 24, when the same man got on at Wimbledon.

"I think he recognised me so he started to make his way over to where I was in the carriage," she said. "It was the same position where he was standing boxing me in but this time not as close.

"I saw that he had exposed himself again in the same manner as last time where he had opened his flies and exposed his genitals through the gap.

"I took my phone out and pretended to be writing a message. It was my intention to unnerve him a little so he would stop what he was doing.

"He turned away from me and moved towards the centre of the carriage. The way he was behaving probably confirms that it was deliberate."

At Waterloo, she allowed the man to get off the train first, then took two pictures of him on her phone, before reporting the incidents to police the next day.

On October 26, she saw the same man on the train. He was standing closely behind a blonde woman in her 20s.

"I noticed that he bent down to put his bag down and ruffled his coat, which would not look out of the ordinary to anyone else," said the woman.

This time, she took more photographs then decided to follow him along Waterloo Bridge and towards the Strand. She lost the man as he was walking "towards the Courts of Justice area".

In December, she saw him again and informed police he was wearing a different three-quarter coat.

Then on January 19 this year, she pointed out the man at Wimbledon station to undercover police. Richards was arrested.

Peter Wright QC, prosecuting, said: "It is the prosecution case that this was no mistaken identification.

"Sadly, and for what we say must be unfathomable reasons, Sir Stephen took the risk of behaving in this way on a crowded commuter train on two occasions to this young woman."

The trial continues.