GSOC said that following a preliminary examination of the incident under section 91 of the Garda Síochána Act, 2005, it was undertaking an investigation under section 98, which, it said, “is for incidents that appear to involve offences”.
GSOC’s statement regarding the location of Hennessy when he was shot differs from some earlier accounts, which suggested he had ran, while holding a knife, at a garda. The ombudsman said it was in the process of obtaining video footage of the incident.
It said a knife was recovered from Hennessy’s Nissan Qashqai and that he had injuries consistent with self-harm.
Hennessy was fatally shot at Cherrywood Business Park, south Dublin, at 8pm last Sunday, over 24 hours after he strangled student Jastine Valdez to death.
GSOC said a postmortem established that Hennessy was shot in the shoulder and that the bullet entered his torso, causing fatal injuries.
It said: “The deceased was in the driver’s seat at the time of the shooting.”
GSOC said its officers recovered a Garda service weapon from the scene and that one spent cartridge and the remaining ammunition was located in the firearm.
After the shooting, there were suggestions Hennessy was armed with a knife and had run either at a traffic garda or the detective when he was shot. There was also a third suggestion that Hennessy was inside the car making stabbing motions.
Garda sources at the time suggested it might not have been clear whether he was stabbing himself or if he might have been stabbing Ms Valdez or could do so. Gardaí at that stage did not know where she was and only found her body on Monday afternoon.
GSOC said a team of officers from Cork were investigating the matter and arrived at the scene at 11.50pm.
The statement said: “Following a preliminary examination of the incident under s91 of the 2005 Act, GSOC is now undertaking an investigation under s 98 of the 2005 Act, which is for incidents that appear to involve offences.”
It said that under this section, GSOC investigators have, for the purposes of the probe, all the powers, immunities, privileges, and duties imposed on members of An Garda Síochána.