With Anthony Weiner's sentencing set for Monday, the big question is: Will he go to prison?

In their sentencing memorandum prosecutors are seeking 21-27 months imprisonment for Weiner, the former US congressman and estranged husband of Hillary Clinton's former adviser Huma Abedin. Prosecutors back up their request by stating, "Weiner, a grown man, a father, and a former lawmaker, willfully and knowingly asked a 15-year old girl to display her body and engage in sexually explicit conduct for him online."

Weiner, 53, pleaded guilty this May in New York's Federal District Court to one count of transferring obscene material to a minor. The charge carries a maximum sentence of 10 years in prison

His attorneys maintain Weiner is not a sexual predator but a sick man who has made "stunning progress" through counseling. They are asking for probation.

The former New York mayoral candidate is in the midst of a divorce from his wife. It is not known if she will attend his sentencing on Monday.

Lewd messages

The facts of the case, according to the government, begin with the 15-year old girl contacting Weiner in the evening of January 23, 2016, by sending him a direct message on Twitter. Over the next few hours Weiner exchanged messages with her that ranged "from the mundane to the provocative."

The government states that although Weiner knew he was communicating with a minor the exchanges became "increasingly suggestive," continuing the next day on Facebook Messenger and then via messaging and photo sharing sites Kik, Confide and Snapchat.

The exchanges continued into February, the government states, even though Weiner knew the girl was a high school student who was getting her learner's permit.

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The government's memorandum goes on to state that in February 2016 Weiner and the girl participated in three video chat sessions on Skype, during which she "made clear that she was ... in fact, only 15 years old." During several of these chats Weiner ""used graphic and obscene language" to ask the girl "to display her naked body and touch herself," prosecutors say.

Weiner also sent her pornography, prosecutors say.

A career collapses

This was all happening under a veil of secrecy, even though Weiner's personal and professional life had been collapsing around him for half a decade.

In June 2011 Weiner was forced to resign from Congress after a lewd picture appeared on his Twitter page. He originally said he was hacked but soon after admitted he had lied but that his marriage to Abedin was intact. His resignation came after photos were released publicly of Weiner in various stages of undress.

Six months later Abedin gave birth to their only child. In July of 2013, two months after Weiner announced he was running for mayor of New York City, a gossip website published screen shots of sexual conversations Weiner had with a woman the previous year.

Abedin joined Weiner for the first time during a press conference, saying that although her husband had made some "horrible mistakes" ..."what I want to say is I love him, I have forgiven him, I believe in him...we are moving forward."

Weiner's mayoral campaign imploded after he admitted to having more lewd conversations with women he met on the Internet. In May of this year, Abedin filed for divorce

"I knew this was as morally wrong, as it was unlawful," Weiner said at his guilty plea in May. "This fall, I came to grips for the first time with the depths of my sickness. I had hit bottom."

'A product of sickness'

In their voluminous, 219-page sentencing document, Weiner's lawyers call his crime "a product of sickness."

"Anthony had already repeatedly been ruined by scandals in which his 'confidential' adult counterparts reported their explicit encounters to the tabloids," they write. "And yet he compulsively responded to this teenage stranger too, under his own name as always, with his self-destructive behavior..."

The defense maintains that Weiner is not a sexual predator. His attorneys say that results of a psychosexual evaluation determined that "Anthony has no abnormal sexual interest in teenagers. His numerous other fantasy sexting partners were adults. He never sought out teenagers on the Internet."

The defense also argues that the girl was the aggressor in their texting and that Weiner "responded to the victim's request for sexually explicit messages not because she was a teenager but in spite of it. He responded as a weak man, at the bottom of a self-destructive spiral, and with an addict's self-serving delusion that the communications were all just Internet fantasy."

Weiner's attorneys say he has finally received counseling for his issues. "The stunning progress he has made is indisputable, testified to by the professionals who have treated him," they say.

But prosecutors argue Weiner's pattern of behavior "suggests a dangerous level of denial and lack of self-control warranting a meaningful incarceratory sentence."

A prison sentence would "promote respect for the law and serve as a deterrent to others who are considering a (similar) path," they say.