Dominique Strauss-Kahn was set to walk free on Tuesday after New York prosecutors said that while the powerful Frenchman did have sex with his hotel maid, they could not prove an assault because the alleged victim's lies undermined the case beyond repair.
Within hours, New York state judge Michael Obus is due to rule on a motion filed by prosecutors on Monday to dismiss all charges against Strauss-Kahn.
The sensational turn around would mean Strauss-Kahn - forced to resign as head of the International Monetary Fund and shelve his French presidential dreams - was free to leave with his millionaire wife back to France.
But the man who had been widely touted to replace President Nicolas Sarkozy in upcoming elections will return with his reputation badly sullied.
The 25-page motion to drop the case concluded that Strauss-Kahn engaged in a hurried sex act May 14 with the Manhattan maid, a Guinean immigrant called Nafissatou Diallo, and that the initial investigation suggested an assault.
DNA testing "established that several stains located on the upper portion of the complainant's hotel uniform dress contained semen that yielded the defendant's DNA," the Manhattan district attorney's Office said in the motion.
Evidence was "consistent with a non-consensual encounter," prosecutors said.
The evidence was not conclusive. For example, there were no injuries or damage to clothing that could only have come from attempted rape.
However, other factors, such as the hurried nature, suggested "that the sexual act was not likely a product of a consensual encounter," the motion said.
Another important piece of evidence was the discovery of Strauss-Kahn's DNA "on both the interior and exterior waistband" of the tights worn by the maid, "as well as on the waistband of the panties."
The motion said, "These findings suggest that the defendant touched the complainant's undergarments, but they do not controvert or confirm the complainant's account that the defendant placed his hand inside her underwear and groped her genitals directly."
In the end, the evidence did not "prove or corroborate that their encounter was forcible or non-consensual."
That meant Diallo's testimony was key to the case - and when it emerged that she had lied to investigators and to the grand jury indicting Strauss-Kahn, the case became impossible to pursue.
One issue was her constantly changing story about what she did immediately after the alleged attack, ranging from hiding fearfully in a corridor to returning to the room to clean after Strauss-Kahn left.
Most seriously, Diallo admitted that she had entirely made up a story during her asylum application to the United States about being gang raped in Guinea.
During one session with prosecutors, she repeated the story with so much emotion that "she cried, spoke hesitatingly, and... even laid her head face down on a table in front of her."
Later, she said "she had entirely fabricated the attack."
A lawyer for the 32-year-old maid hit out angrily after being told of the decision at the prosecutors' offices in Manhattan, where a media scrum and hundreds of onlookers greeted their arrival.
"The Manhattan district attorney, Cyrus Vance, has denied the right to a woman to get justice in a rape case," Thompson said after the brief meeting, which lasted less than 15 minutes.
Thompson accused Vance of having "turned his back" on forensic, medical and other physical evidence.
Diallo, wearing black trousers and a beige jacket, and accompanied by several hulking private security guards, said nothing.
Strauss-Kahn's legal team, however, said the former French politician was "grateful" that New York prosecutors concluded "that this case cannot proceed further."
"We have maintained from the beginning of this case that our client is innocent," said lawyers William Taylor and Benjamin Brafman.
He could now in theory return to frontline French politics, but no one back in France is expecting a prominent role.
"I don't think he can hope for a center stage role in French politics now," said political scientist Gerard Grunberg of the prestigious Sciences-Po school in Paris.
"His public image is much deteriorated and the Socialist Party and its leaders must be mad at him for having missed this moment of opportunity. Neither the public nor the party want to see him back on the frontline."
His legal travails are also far from over.
Diallo has filed a civil suit seeking unspecified damages against Strauss-Kahn. Thompson also plans to ask the judge overseeing the case to appoint a special prosecutor because he believes Vance had mishandled the case, although legal experts said this effort would almost certainly go nowhere.
Diallo's French lawyer was to file a separate complaint on Tuesday, accusing a deputy mayor in Sarcelles, near Paris, of pressuring a woman who claims to have had a liaison with Strauss-Kahn not to give testimony.
And despite the apparent collapse of the New York case, he could still face further sexual assault charges when he returns to France.
In one case, 32-year-old writer Tristane Banon has filed a complaint alleging the 62-year-old Socialist politician tried to rape her after luring her to a Paris flat in 2003.
He denies the claim, and she may have difficulty convincing prosecutors to pursue the case so long after the alleged incident, but the magistrates are looking into it.
In a separate action, Strauss-Kahn has announced his intention to sue Banon for defamation, alleging she invented the story to help publicize her writing.