Once he went to Washington and stayed a month. It was during that time that his friend Dr. Cox was assassinated. A client of Marcum's by the name of Mose Feltner came to his home to acquaint the lawyer with a plot against his life. Mose told how he had been given thirty-five dollars to commit the deed and a shotgun for the purpose. He also took Marcum to a woods and showed where four Winchester rifles had been concealed by him and his three companions. The guns, Mose said, were kept there during the day but were carried at night so that if he or his companions met Marcum they were prepared to kill him. The plot, so Mose declared, was to entice Marcum to his office on some pretext or other. Mose was to waylay him and pull the trigger. Mose went further. He told Marcum that the county officials had promised him immunity from punishment if he would carry out the plot and kill Marcum. When at last the election contest furore had quieted down Marcum concluded it was safe to venture forth to his law office and resume his practice. On the morning of May 4th he had gone to the courthouse to file some papers in the case. He lingered for a while in the corridor to greet this one and that, then walked slowly through the corridor toward the front door. From where he stood talking with a friend, Benjamin Ewen, Marcum could see across the street Judge James Hargis and Sheriff Ed Callahan sitting in rocking chairs in front of Hargis's store. When the shots were fired that killed Marcum neither Hargis nor Callahan stirred. Their view was uninterrupted when the lifeless body plunged forward. They remained seated in their rocking chairs, looking neither to right nor to left. They made no effort to find out who did the shooting. "My God! they have killed me!" cried Marcum as bullets struck through the spine and skull and he lunged forward dead. Curt Jett, tall and angular with red hair and deep-set blue eyes, a man of many escapades, was convicted of the murder and sent to the penitentiary for life. The evidence of Captain B. J. Ewen, with whom Marcum was talking when shot, disclosed that Tom White, one of the conspirators, walked past Marcum glaring at him to attract his attention. As he did so Curt in the rear of the hallway of the courthouse fired the shots. Curt Jett's mother was a sister to Judge Hargis, and Curt, though only twenty-four at the time, was a deputy under Ed Callahan.