The lawsuit follows criminal charges against a Lisle man accused of operating a high-powered pontoon while intoxicated before the July 25 collision.
MCHENRY, Ill. — The family of 48-year-old U.S. Marine veteran Magdalena Jablonska has filed a wrongful death lawsuit after authorities said a speeding pontoon boat struck and rode over the smaller vessel she shared with her fiancé on the Fox River, killing her and injuring him.
The civil case adds a second legal front stemming from the July 25 collision south of the McHenry Dam. Richard M. Stevenson, 45, of Lisle, already faces two counts of aggravated driving under the influence causing death and one count of reckless homicide. Prosecutors allege Stevenson was intoxicated and traveling at an extremely high speed when his 31-foot South Bay pontoon struck the rear of a 20-foot Crownline in a no-wake area. Stevenson remains detained while the criminal case proceeds and is presumed innocent unless proven guilty.
Illinois Conservation Police officers responded to the crash at about 2:30 p.m., according to the McHenry County State’s Attorney’s Office. Officers found the Crownline severely damaged and Jablonska dead aboard the vessel from catastrophic injuries. The larger pontoon had run aground nearby. Authorities said Stevenson was later located among trees near the shoreline where his boat had stopped. Two other people who had been aboard the pontoon left the area before officers arrived, prosecutors said.
Stevenson was taken to Northwestern Medicine McHenry Hospital after the crash. Prosecutors said evidence presented during his detention hearing showed a blood alcohol concentration of about 0.200. Multiple witnesses told investigators that Stevenson had consumed alcohol during the day and had operated the pontoon at high speeds on the Chain O’ Lakes and Fox River shortly before the collision. Prosecutors have said the boat was traveling about 80 mph, while the civil lawsuit alleges Stevenson was moving at more than 75 mph as he approached the no-wake zone.
Jablonska, of Des Plaines, had been spending the afternoon on the river with her fiancé, Alan Telmini, and their dog, Sasha. According to the lawsuit and family accounts, the Crownline was moving slowly through the no-wake area when the larger boat approached from behind. Telmini survived the collision but was injured. He later said at a news conference that he continues to relive what happened and that the couple had simply planned to enjoy a summer day on the water.
The wrongful death suit accuses Stevenson of failing to operate the pontoon safely and seeks damages connected to Jablonska’s death, Telmini’s injuries and emotional distress. Lawyers for Jablonska’s family have said their investigation is also examining whether any other individuals or entities could bear civil responsibility. The civil allegations have not been adjudicated, and the lawsuit remains separate from the criminal prosecution.
Jablonska was born in Poland and later moved to the United States. She joined the U.S. Marine Corps after high school and served for six years before receiving an honorable discharge, according to her family and attorneys. She later worked for Servpro and was active in the Women Marine Association. Relatives described her as generous and devoted to helping family, friends and animals, including dogs in need. A visitation for family and friends was scheduled for Aug. 9 in Park Ridge.
The criminal case has continued to move through McHenry County Circuit Court. At an Aug. 4 hearing, Judge Mark Gerhardt granted in part a defense request to preserve evidence connected to the investigation. The order directed several law enforcement agencies to retain relevant video and audio recordings and required DUI testing materials to be preserved for possible future testing and analysis.
Stevenson was ordered detained before trial after prosecutors argued that his release would present a threat to public safety. At the detention hearing, prosecutors also cited previous charges involving driving under the influence, reckless driving and speeding. Those prior cases do not establish guilt in the July 25 collision. The State’s Attorney’s Office has emphasized that the current criminal charges are allegations and that Stevenson is presumed innocent unless prosecutors prove the charges beyond a reasonable doubt.
Stevenson remains in the McHenry County Jail and is scheduled to return to court Aug. 21 for a preliminary hearing. The criminal investigation and wrongful death litigation are continuing as authorities and attorneys preserve evidence and examine the events leading to the collision.
Author note: Last updated August 8, 2026.