Haughton, Goudreau and Smullen were all wearing a Caliente helmet (which, after the fact was discovered to be no more durable than a child's bicycle helmet.) After Haughton's death in 1986, the following study was conducted to help prevent this in the future: (copied from the abstract at the NIH):
"A case of a harness racing accident in which the driver died of head injuries is presented. To evaluate the victim's head injury and corresponding helmet damage, a videotape of the race was reviewed and analyzed. Based on calculations of a simplified trajectory analysis and testing of the helmet, it was determined that the helmet design did not provide adequate protection for the victim.
The standards for harness helmet design are being re-eval-uated by the harness racing industry to ensure the safety of the drivers. A review of 178 harness racing injuries and deaths, current harness helmet research, and recommendations for safer helmets are discussed. A protocol for the forensic investigation of sports-related injuries and/or deaths is also presented to assist medical examiners in fulfilling their roles as practitioners of preventive medicine.
The American Journal of Forensic Medicine and Pathology 8(3):p 185-207, September 1987."