Louis Walsh's accuser was proven to be a complete liar when CCTV images of the night in question where showen.
The footage shows Louis chatting away with pals, including Westlife star Shane Filan, around the time it was falsely claimed he assaulted a man.
When detectives confronted dancer Leonard Watters with the sequence of events, he cracked and admitted he made the whole thing up.
The series of photos show Louis on the night that nearly wrecked his career.
We see him chatting casually with pals and in total control of the situation. At no stage is Louis even seen having a drink.
He is seen laughing and joking with friends at celebrity haunt Krystle after another successful night by Westlife at the 02.
The pictures proved to gardai that Louis was completely innocent of the accusations.
The photos also formed part of the evidence officers used to confront Louis' accuser, Leonard Watters (24).
Watters was today still being questioned by detectives at Pearse Street Garda Station.
He was arrested at noon yesterday after admitting he lied about being assaulted by the X Factor judge.
"The black and white pictures show a man on a normal night out with pals," said a source close to the inquiry, referring to Louis.
"He looks like he is in great form, with not a care in the world. Everyone is having a great time, joking and chatting.
"There is nothing at all irregular about the situation, and that's what proved that Watters had made the whole thing up," said the source.
"Louis wasn't even drinking and was totally sober. The situation Watters had painted just did not add up. It would have been totally at odds with what is shown in the photos," said the source.
Louis is seen with Westlife member Shane Filan and a group of pals.
Today Shane said he always knew that Louis was "100 per cent innocent" because he was with him at the critical time.
Shane condemned the man who made false accusations of sexual assault against his longtime manager, saying that Louis was "punished" for his generosity and kindness.
"Louis is a man whom I admire and respect more than any in the business and have grown to love over 15 years," Shane said.
"He's also the most professional and well behaved guy in showbiz. I've never once seen him drunk in over a decade of knowing him.
"Hardly the behaviour of a wayward, out-of-control predator is it?
"I spoke to Louis the day the story broke. He sounded heartbroken and distraught. I've never heard him so hurt and vulnerable.
"But like with all good people, it didn't take long for people to rally and publicly support Louis. I, and the Westlife boys, were among them."
He emphasised that Louis was in the company of close friends on the night and that he never saw him speak to the 24-year-old father-of-one, who has subsequently been arrested for making a false statement.
"This guy came up, Louis wasn't talking to the guy any more than the rest of us. I didn't see him go off with this guy. Not to the toilets or anywhere."
The singer said that his manager of 15 years has the true "X Factor" due to his "incredible" nature.
"We were with him on the night this so-called incident happened, after all, and we knew he was 100pc innocent," he added. "That has now been proven beyond doubt. But what is sad about all this is Louis has been punished for being one of the most giving, open figures in showbiz.
"He made time for everyone. How did he get rewarded? By being tortured and tormented by a nightmare.
"Despite this, I have no doubt Louis will now bounce back and still remain the incredible music man and human being I have known for years. Now that really is the X Factor."
Simon Cowell today expressed "delight" at the outcome and says he always knew "this was a load of rubbish".
The X Factor boss, who is currently in the US, said: "Louis is a good friend of mine and I think the world of him. I am so pleased that everyone now knows it is a load of rubbish as well. I am so pleased for him and I look forward to seeing him soon.
"I have spoken to him and I know he is very happy."
Detectives were today still questioning accuser Watters for making a false statement and sources are confident he will be charged before the courts within the next 24 hours.
Gardai expect he will charged under section 12(a) of the Criminal Law Act 1976 -- which is the offence of making a false statement to gardai and carries a maximum sentence of five years in jail.
He was detained at his home in Navan, Co Meath, less than 12 hours after he admitted that he had lied about Louis Walsh.
He originally told gardai he went to the toilets in Krystle when Walsh appeared behind him and allegedly molested him. He left the nightclub and then, on the street outside, he reported the 'incident' to a uniformed garda patrolling the area. Watters then went to the Mater Hospital where he was examined for evidence of a sexual assault.
Staff at the hospital reported the complaint to the local garda station in Fitzgibbon Street. The complaint was taken by Pearse Street Garda Station. Louis's accuser made a formal statement to detectives there last week. After this happened, a major investigation kicked off involving dozens of detectives.
Sources have revealed that officers visited Krystle nightclub at Harcourt Street at least four times in the past week where they obtained CCTV and examined the nightclub in huge detail.
As part of their investigation, detectives met Louis Walsh at the Four Seasons Hotel in Ballsbridge on Friday where he gave officers a full account of his activities and movements in the early hours of April 10.
Sources say that at that stage Watters continued to "stick to his story" and the most likely outcome at that point was that a file would be prepared on the matter for the DPP to determine if charges should be brought against Walsh.
But as detectives continued to probe the case in huge detail on Monday evening, they decided to visit Mr Watters' home in Navan, Co Meath to interview the victim.
It was while being grilled here that Watters finally cracked and admitted that Walsh had not in fact assaulted him.
Instead he told gardai that he was indecently assaulted in the nightclub in the early hours of April 10 but that Louis Walsh was not responsible for it. Sources say gardai do not believe that Watters was assaulted at all.