Mr Tomlin was 32 when he died after being pinned down and arrested by officers in Haywards Heath in July 2014.
Over the last four weeks a jury inquest has been taking place at Centenary House in Crawley to try and establish how he died.
This morning the last piece of evidence was heard and assistant coroner Elizabeth Bussey-Jones began her summing up of the case for the jury.
She said: “You must set aside feeling and sympathy for anyone involved in this inquest.
“You are not trying issues between parties deciding if somebody is innocent or guilty or whether someone is liable or not.”
Seizures are 'extremely traumatic'
One final piece of evidence was heard this morning, in which Ms Bussey-Jones said that all parties had agreed that Tasers were not used in the incident.
Ms Bussey-Jones then began the process of recapping each piece of evidence and witness account for the jury.
Paul Tomlin, Mr Tomlin’s father, was summarised as saying that son’s seizures were ‘not what one imagines’: “It is not just falling into the street and kicking out, it varies.
“It is extremely traumatic, a mixture of terror, fear and shock.”
'His behaviour started to become less coherent. He was paranoid'
Jack Fulger, who had been drinking with Mr Tomlin and others on the night he died, had described how he started acting ‘weirdly’ after taking cannabis.
He was summarised as saying: “Duncan was sort of breathing really heavily.
“His behaviour started to become less coherent. He was paranoid.”
The jury heard Mr Fulger’s recollections that Mr Tomlin had been threatening to kill the people in the house and was screaming.
A neighbour heard ‘a lot of thumping as if somebody is being pinned up against the wall’ and called the police, the inquest was told.
She described seeing a man push Duncan out of the house and close the door.
A woman arrived soon after at the scene and asked one of the people in the house if Duncan was having a seizure. They replied: “No he’s not having a seizure he’s been drinking.”
PC Watson: 'Duncan punched me'
The evidence of PC Watson – the first officer involved in the restraining of Mr Tomlin – was also summarised.
The inquest heard that he and others were at Haywards Heath Police Station when they were called to a ‘disturbance’ in Wood Ride.
When he got there he saw Mr Tomlin running away and gave chase.
“Duncan turned and with his right hand punched me to the left side of my face
“The punch heard and shocked me as I wasn’t expecting him to attack me.”
The inquest heard that PC Watson did not think Mr Duncan was having a seizure, rather that he thought he was on drugs due to the ‘immense strength’ he had.
He denied that he failed to explore the ‘seizure issue’ with Anne-Marie Botting, Mr Tomlin’s girlfriend.
“I don’t accept that I failed to tell Police Sergeant Glasspool relevant information.
“I don’t accept that I lost my temper and control.”
Off-duty detective helps out officers
Off-duty detective David Shabazi – who went over to assist the officers restraining Mr Tomlin – said Mr Tomlin displayed ‘extreme strength’.
The inquest heard that he advised the other officers that Mr Tomlin needed to be sat up.
“It was a difficult situation. I did say it to them but they did not respond and I did not reinforce it.
“I didn’t know he was going to die. I suggested the ambulance because in my view he needed urgent medical assistance.”
Neighbours describe the struggle
Carol Anderson, who lived near where the restraining incident took place in the street, was summarised as saying: “She heard him saying ‘get off me I’m ill’ and then she heard a wailing sound.”
Ms Anderson said she saw officers pinning Mr Tomlin on the ground while they waited for a police van to arrive.
She added: “The man was not kicking or flailing as he was put in the van.”
Another neighbour, Storm Croydon, said she saw the van stop at one point after it set off.
“The officers acted like they were in a state of concern or emergency and went off up our road.”
Assistant coroner Ms Bussey-Jones is expected to finish summing up the evidence tomorrow, after which the jury will be sent out.
The inquest continues.