Police said Alexis Trader, 34, was arrested Wednesday and has been charged with one count of murder.
Police said Trader battered 63-year-old Nabil Abzal on Aug. 30, 2025, causing him to fall into Lake Michigan and drown on Labor Day weekend.
Abzal of Plainfield was affectionately known as "Captain Bill."
Trader, who appeared in court Thursday, has a long criminal history.
Trader was already in Cook County Jail for an unrelated crime, when he was charged in Abzal's death.
A judge Thursday ordered Trader to remain behind bars, pending trial.
Prosecutors say Trader was with another man and two women in the early morning hours of Aug. 30 at DuSable Harbor, when they decided to sneak onto the dock so the women could take pictures on one of the yachts for social media.
Investigators say the women boarded a yacht there, not knowing Abzal was sleeping onboard.
Abzal woke up, and he allegedly asked them to leave.
As Abzal escorted the women off the dock, prosecutors say Trader punched him in the face, causing him to hit his head on the dock and fall in the water.
Authorities say video and audio of the attack were captured by a security camera at a nearby restaurant.
They said Trader called 911 but gave police a false name.
Several witnesses later identified him, and police located him through phone records.
Prosecutors say Trader has a history of violence and a lengthy criminal record, dating back nearly 20 years, including burglary and armed robbery.
Abzal's friends are relieved he's finally getting some justice.
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