Peter Dale MacDonald was charged in October with three counts of first-degree murder in the deaths of Julieanne Middleton, 23, Virginia Coote, 33, and Darlene MacNeill, 35, The Globe and Mail of Toronto reported. All three were sex workers from Toronto's Parkside neighborhood; their bodies were found in Lake Ontario.
Prosecutors told the court Friday there was not enough evidence against MacDonald to proceed to trial. The investigation into the three deaths is ongoing.
MacDonald, once named one of Prince Edward Island's "most notorious criminals" by The Guardian, is already serving time in prison for a previous murder, and will stand trial in 2012 on another murder charge.