The Somerset County Prosecutor's Office released the results from the investigation into the deaths of John Sheridan, former head of South Jersey's top trauma center, and wife Joyce Sheridan.

The investigation concluded that John Sheridan, former Cooper Health University System CEO and former New Jersey Department of Transportation Commissioner, stabbed his wife before killing himself in their Montgomery Township home on Sept. 28, 2014. The results of the investigation were announced Friday, after the Somerset County Prosecutor's Office and the Montgomery Township Police Department conducted more than 180 interviews with potential witnesses and examining scores of evidence.

The Sheridans' four sons challenge the results of the investigation, categorizing it as an "embarrassing bungling", according to MyCentralJersey.com. "To be clear, we do not have answers to what happened to our parents," the Sheridans' sons said Friday in a statement, according to MyCentralJersey.

Some of the major findings of the investigation include:

Joyce Sheridan suffered a number of wounds, including eight wounds to her head, five of which were incised wounds. Three of the wounds were stab wounds. She also suffered a stab wound to her chest, which ruptured her aorta.

John Sheridan was found with five superficial wounds, consistent with self-infliction. He did not have any defensive wounds. However, there was one wound on his neck, which perforated the right jugular vein and would have been fatal without medical treatment.

There was no evidence of a third party or of forced entry into the Sheridan's residence. Additionally, authorities ruled out the possibility of burglary.

Authorities recovered various items from the scene, most significantly, knives, accelerant, and matches which all belonged to the Sheridans and were located in the residence.

Family members and colleagues said John Sheridan's behavior and demeanor in the days leading up to the incident was materially different than his norm. Firefighters responded to the residence during the morning of Sept. 28, after receiving reports of a house fire. The first responding police officers were unable to access the second floor of the home, due to heavy smoke.

After equipping breathing apparatuses, firefighters were able to access the second-floor bedroom, where they discovered John and Joyce Sheridan.

John Sheridan was discovered face up on the floor at the foot of the bed, with a n armoire resting on top of him. Autopsy results concluded that John Sheridan was alive after the fire was started. His cause of death has been classified as a suicide.