CHICAGO (AP) – Federal prosecutors are seeking a 40-year prison sentence for man found guilty of sex-trafficking a Chicago teenager who was murdered.

Joseph Hazley was found guilty in March of sex-trafficking 16-year-old Desiree Robinson and two other victims. Robinson was allegedly killed in December 2016 by a man who answered an online sex advertisement.

Desiree Robinson (provided photo)

Although Hazley wasn’t charged directly in Robinson’s death, prosecutors contend the case is a reminder of the danger faced by sex trafficking victims. In his filing, defense attorney Raymond Wigell wrote Hazley has mourned woman’s death.

RELATED: Chicago man Convicted In Sex Trafficking Case Involving Murdered 16-Year-Old Girl

Antonio Rosales is awaiting trial on first-degree murder and aggravated sexual abuse charges in Robinson’s death.

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