Mr Gilheaney was arrested in Lincoln’s Inn Fields.
During his arrest, according to the prosecution, he told officers: “I am so sorry for everything I have ever done. I will admit to everything. I am guilty. I am sorry.”
In another police interview he is alleged to have told officers he could not remember the events on Christmas morning.
A blood sample was taken from Mr Gilheaney which was found to contain 147mg of alcohol per 100ml of blood. The legal limit is 80.
Another blood test revealed the defendant had taken a medication for treating conditions like nerve pain, anxiety disorders and epilepsy, the court hears.
Mr Gilheaney also denies one count of wounding with intent, two counts of causing grievous bodily harm with intent and one count of attempting to cause grievous bodily harm.
Jurors were told he already admitted to dangerous driving.
The trial continues.