Arsenic poisoning: acute or chronic? Suicide or murder? The case of the death by arsenic poisoning of a 62-year-old white man is presented. One year prior to death, he developed intermittent bouts of severe gastroenteritis with vomiting and diarrhea, hyperpigmentation and keratosis of the skin, neutropenia, and Guillain-Barre-like neuropathy for which he was hospitalized several times. Urine test results 6 months prior to death indicating 36 mg/L arsenic were believed to be in error. At the patient's last admission, he appeared in the emergency room with severe gastroenteritis, hypotension, and dehydration. He died 3 days later. Antemortem as well as autopsy specimens revealed elevated arsenic concentrations. Arsenic micrograms/g analysis by neutron activation of hair pulled from the man's head revealed by centimeter segmental analysis proximal to distal: 226, 104, 28, 56, 41, 40, and 74. The wife of the decedent was charged with murder by arsenic poisoning of this, her fifth, husband. The defense alleged that the decedent had committed suicide. The judge awarded a directed verdict of "not guilty." Particulars of the medical, toxicological, and investigative findings are presented. 