NEW YORK (CBSNewYork/AP) — Former U.S. Rep. Anthony Weiner‘s 21-month prison sentence for having illicit online contact with a 15-year-old girl is set to end Tuesday.

Weiner was ordered to register as a Level 1 sex offender – meaning he’s thought to have a low risk of reoffending.

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He has been staying at a Brooklyn halfway house.

Weiner must register for a minimum of 20 years. He’s required to verify his address every year and visit a police station every three years to have a new picture taken.

A once-rising star in the Democratic Party who served nearly 12 years in Congress, Weiner had a dramatic and sordid fall from grace after he sent a lewd picture of himself to a college student over Twitter in 2011.

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Weiner initially claimed his account had been hacked, then admitted he’d had inappropriate online interactions with at least six other women while married to top Hillary Clinton aide Huma Abedin.

Former US Congressman Anthony Weiner leaves Federal Court in New York on May 19, 2017. (Photo credit TIMOTHY A. CLARY/AFP/Getty Images)

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Weiner resigned from Congress that year but mounted a campaign for New York City mayor in 2013.

WEB EXTRARead Weiner’s complete remarks (.pdf)

But his personal behavior was again his undoing after it was disclosed he sent explicit photos under the alias “Carlos Danger” to at least one woman after resigning from Congress.

Weiner ultimately garnered less than 5 percent of the vote in the Democratic primary.

His final fall came in 2017 after prosecutors say he sent a series of sexually explicit messages to a North Carolina high school student. Weiner pleaded guilty to transferring obscene material to a minor.

At his sentencing, he said he’d been a “very sick man for a very long time” because of his sex addiction.

Weiner’s attorney said the ex-lawmaker likely exchanged thousands of messages with hundreds of women over the years and was communicating with up to 19 women when he encountered the teenager.

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(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)