One of Britain's most senior judges has been cleared of exposing himself twice to a woman on packed commuter trains.
Sir Stephen Richards, 56, of Wimbledon, south-west London, was accused of flashing at the same woman on trains in the area on 16 and 24 October 2006.
But the Court of Appeals judge told magistrates the allegations were a case of mistaken identity.
City of Westminster magistrates said the evidence to identify Sir Stephen was insufficient.
They said in the absence of any evidence supporting the judge's identification and "for this reason only" they could not be satisfied beyond reasonable doubt.
After hearing the evidence, Senior District Judge Timothy Workman said the case came down to Sir Stephen's word against the woman's.
However, he said the woman, a City worker in her 20s, gave "clear, dignified and truthful evidence".
He blamed British Transport Police (BTP) for failing to investigate the allegation promptly or thoroughly.
"Had they done so, they would have been able to obtain CCTV from the train on October 24 and probably on October 16," he said.
"That evidence may well have supported her identification and, equally, may have exonerated Sir Stephen."
The woman made her initial complaint on 25 October 2006 but the trains' CCTV footage, which is wiped out after five days, was not examined.
A BTP spokesman said the force had accepted the failings highlighted by the judge during the court case.
She told the BBC News website: "Because of a heavy case load it was not practical or possible for the officers to seize CCTV before it expired."
Speaking outside the court beside his wife Lucy, Sir Stephen said: "Throughout this case, I have put my trust in the legal process and I'm delighted that it has enabled me to clear my name.
"Lucy and I would like to express our deep gratitude to our family and friends for their tremendous kindness and support over the last few weeks.
"We look forward to resuming a normal life and in my case in getting back to my full judicial duties."
During the three-day trial, the court heard the woman had allegedly captured Sir Stephen on a mobile phone and identified him at a video identity parade.
Sir Stephen had pleaded not guilty to two counts of "intentionally exposing his genitals intending that someone would see them and would be caused alarm or distress".
The father-of-three told City of Westminster Magistrates' Court he could not "perceive deriving any form of gratification" from such an act.
While giving evidence, Sir Stephen held up a pair of Calvin Klein underpants similar to those he wears to show the difficulty of exposing himself in them.