The confessions were signed in the stockade at Fort Dix in the winter of 1943 and 1944. Private Clarence Hill, thirty-three, a Black soldier from Hamilton Township, New Jersey, put his name to statements covering every attack the police had laid to the man the newspapers called the Mad Killer of Duck Island. Six people had died in three shotgun attacks on couples parked in lovers' lanes around Trenton between 1938 and 1940, and there had been attacks since in which couples survived. Hill later said the statements had been beaten out of him. Doctors who looked into his account of the beatings disagreed with one another, and the court ruled that his typewritten confession had not been made under duress.
Duck Island was a former landfill on the Delaware River at the edge of Trenton, a place couples drove to at night, many of them, as it turned out, people who were not supposed to be together. On November 8, 1938, Vincenzo "Jim" Tonzillo, twenty, a married man, was parked there with Mary Myatovich, fifteen or sixteen (the sources differ), when a man with a 12-gauge shotgun, later described as short and stocky, came up to the car and demanded money. Tonzillo refused and was shot dead. Mary ran, was shot in the lower body, chased down and raped. Police found her after reports of screaming; she lived long enough to tell them what had happened, though at first they doubted her, and died the next day.
On October 1, 1939 a junk collector on Duck Island saw a woman's artificial leg sticking out of a pile of garbage. Nearby was a car holding the body of Frank J. Kasper, twenty-eight, a mechanic, killed by shotgun blasts to the head and neck the night before; the name also appears as Casper. Katherine Werner, thirty-six, was found not far off, her skull crushed as she tried to run. Both were married to other people, and both spouses had alibis. Couples stopped going to Duck Island. In 1940 two more couples parked elsewhere around Trenton were approached by a Black man with a shotgun, and a nineteen-year-old, Howard Wilson, was shot in the arm. On November 16, 1940, Ludovicum J. Kovacs, thirty-five, and Caroline Moriconi, twenty-seven, also involved in an affair, were found shot dead in their car in a wooded spot off Cypress Lane in Hamilton Township. The ages given for the later victims vary from source to source, sometimes by a decade. The detective in charge described the killer as a lunatic driven by sex mania.
The break, as the prosecution presented it, came from the last attack. On March 7, 1942, near Morrisville, Pennsylvania, across the river, John Testa, twenty-five, and Antoinette Marcantonio, twenty-one, were robbed of $9.30, fired on, chased and beaten with the stock of a shotgun. Both survived. A broken piece of the stock carrying part of a serial number was recovered, and investigators said it led them to Hill, who had been drafted into the Army on March 12, 1943. Most accounts date his arrest to December 29, 1943, at an Army camp at Moultrieville, South Carolina, from which he was taken to Fort Dix; some give January 28, 1944. He was arraigned in Hamilton Township police court on six counts of murder.
At trial in Mercer County the case against him rested on the confessions. There was no murder weapon in evidence and no eyewitness who could put him at a killing. He was tried for the murder of Mary Myatovich, and on December 29, 1944, a year to the day after the arrest date most sources give, the jury found him guilty of first-degree murder and recommended mercy. He was sentenced to life at hard labor. A writ of error was dismissed in February 1947 for failure to prosecute it.
He had been a barber, and he was remembered in the press of the time as a father of two and a former Sunday school teacher. His cause was taken up by Leon Josephson, a New Jersey lawyer who spent decades on the case. Josephson's papers, later worked into a book by his son Lee, argue that Hill was framed: that the police needed a man for a series of attacks on white couples and found a Black soldier. The book quotes Hill as saying that he would not let stand the story that "a normal Negro is really a murdering monster." None of that has been tested in a court, and the conviction stands.
Hill was a model prisoner and was repeatedly denied parole. On April 19, 1964, after nearly twenty years, he was released on medical parole with throat cancer. Pennsylvania asked to extradite him on the Morrisville attack and older charges, and Governor Richard J. Hughes refused. Through Josephson he was treated at Memorial Sloan-Kettering in New York, where, unable to work as a barber with a hole in his throat, he was given a job sweeping floors on the wards.
He died of cancer in Trenton in July 1973, aged sixty-two, on the ninth by some records and the tenth by others. His birth is given as November 10, 1910, in Atlanta, which matches his age at arraignment; a 1929 birth year that circulates online would have made him nine at the first killing and cannot be right.