Former firearms officer Andrew Hurley, 34, claims he suffered post-traumatic stress because he was not properly cared for after the shooting and is suing Gwent Police's chief constable.
Pc Hurley had shot Cemalettin Ortancil, 19, who was armed with a replica Magnum revolver, as he tried to get away with £9,000 from a bank in Newbridge, south east Wales, in October 2000.
Ortancil was later given 11 years youth custody.
Pc Hurley is claiming £250,000 for loss of earnings and pension rights after leaving his job five months after the shooting suffering from stress
He was the first officer from the force to shoot a criminal.
The father-of-two claims he did not receive proper counselling after the incident, for which he was given a commendation award.
"
We were told in no uncertain terms that we risked being arrested to get our
blood
"
Pc Andrew Hughes
Cardiff County Court was told by Mr Hurley's colleague, Pc Andrew Hughes, that Mr Hurley was kept isolated from the other officers after the incident, and that they had been told they could be arrested if they refused to give blood samples.
Pc Hughes told the court how he and another officer, David Haywood, were told to stay in a lecture theatre at the Gwent Police headquarters while Mr Hurley was kept on his own in the firearms office.
"We were kept apart," said Pc Hughes.
"We were stopped from going to wash the blood off our hands.
"We were told in no uncertain terms that we risked being arrested to get our blood.
"We were offered white suits, the same that murderers and rapists are.
"
We were in a very confused and traumatised condition
"
Pc David Haywood
"I would say that was insensitive and uncaring."
Another colleague Pc Haywood, a firearms officer for 10 years, told the court they had been kept in the lecture theatre for at least an hour.
He said: "We were constantly asking to see Andrew Hurley and we knew that he must be in an absolute state of shock, and be beside himself with worry.
"Nobody would allow us to go near him.
'Too little'
"There came a time when we were allowed to see him but it was too little, too late.
"We were in a very confused and traumatised condition."
They were later told that there was no threat of arrest but Mr Haywood said he still believed it had been implied initially.
"It was distressing enough for us, so God knows what it must have been like for Andy sat in the office on his own," he said.
Mr Hurley carried on working after the incident but "wasn't himself", Pc Haywood said.
'Traumatised'
He added: "I think he was suppressing his feelings. He certainly wasn't himself.
"He was traumatised. He was neglected.
"If he had been properly treated after the incident, had there been a post-incident procedure in place, I would still be working with him."
A proper debriefing was organised more than two months after the incident on a weekend when the officers involved had all booked time off and were unable to attend, Pc Haywood said.
But Chief Superintendent Joy Lott, who had overall responsibility for the officers after the incident, said the procedure she had employed was in line with the relevant chapter of the manual on police use of firearms and Gwent Police's own firearms policy.
"I accept there was not an individual force procedure in relation to post-incident procedures," she said.
Trained
The officers involved in the incident had been trained under the Essex Constabulary's procedure, which Gwent Police has now adopted with some modifications.
Chief Supt Lott also said she had offered Pc Hurley counselling but that he had refused it.
Pc Hurley is claiming the damages from Gwent Police's Chief Constable Keith Turner.
Gwent Police dispute the claims and the case is continuing.