Police and paramedics rowed over whether a Novichok victim had been poisoned by the nerve agent, an inquiry heard.
There were “heated” conversations between a paramedic and police officers who were not wearing personal protective equipment while Charlie Rowley was being treated, the inquiry into the death of his partner Dawn Sturgess heard.
Police initially suspected Mr Rowley had suffered a drug overdose.
Ms Sturgess, 44, died after she was exposed to the chemical weapon, which was left in a discarded perfume bottle in Amesbury, Wiltshire, in July 2018.
All three survived, as did Ms Sturgess’s boyfriend, Mr Rowley, who had unwittingly given her the bottle containing the killer nerve agent.
On Friday, the inquiry heard that when police arrived at the property in June 2018 the paramedics already there presumed the two officers would be in protective equipment.
But they arrived without it, and paramedic Ben Channon said he was “fearful for their safety and advised them that they needed to don appropriate personal protective equipment before coming forward”.
Mr Channon said the officers were “overly confident that this was likely a drug overdose as opposed to anything else”.
Mr Channon told the inquiry he was “quite frightened at the time” and asked what was making the officers think it was something other than nerve agent poisoning.
He added: “And I can’t recall the conversations, but I remember them becoming heated, but not rude, as to ‘we’re really concerned, please could you share some information with us as to why you’re so certain that this is not nerve agent poisoning’.”
One of the paramedics said to him “what gives you the right to question our clinical judgment?”, Emilie Pottle, counsel to the inquiry, said. Sergeant McKerlie replied that he “never questioned their medical judgment”.
Sergeant McKerlie said he still thought the cause was a drugs overdose, but began having “reservations” when he began asking questions and they were “quite insistent”.
Before he went in the flat, Sergeant McKerlie said he was told by a colleague there was some “drugs intelligence pertaining to that address and to the people”.
Asked if he should have, in hindsight, given more weight to their clinical assessment of what was causing Mr Rowley’s symptoms, he said: “In hindsight, yes, as I said, I just started to have reservations, and it was something that, you know, I wanted to discuss with a duty inspector as and when he arrived on the scene.”
Earlier in his evidence on Friday, Mr Channon described Mr Rowley as acting “grossly abnormal” compared with anything he had encountered before.
Mr Channon said he found Mr Rowley “up against a wall” with his hands “almost as if he was climbing down the wall” and “making noises very much like a cow”. The paramedic also noticed “profuse amounts of saliva coming from his mouth”.
He remembered he and his ambulance colleague “looking at each other and being very concerned that this behaviour was grossly abnormal in comparison to anything that we perhaps encountered before”.
Mr Channon assessed Mr Rowley, donned personal protective equipment and updated the control room, as he was concerned it could be poisoning from a gas leak and poisoning from an unknown substance, the inquiry heard.
And having worked locally after the Salisbury poisonings a few months previously, that was the “immediate concern”, Mr Channon added.
In his witness statement, read out by counsel to the inquiry Francesca Whitelaw KC, he said he thought the symptoms were “not the normal presentation of a drugs overdose, which we thought it initially could have been”.
Paramedics administered Naloxone to treat a potential opioid overdose, but it “did not have any effect”, the inquiry heard.
Mr Channon said: “At that point, (colleague) Mr Martin and I came together, and Mr Martin suggested, he said, this is very similar to what we learnt about following the Salisbury incidents.”
Mr Rowley was then given atropine which would treat the symptoms of nerve agent poisoning, the paramedic added.
Inspector Marcus Beresford-Smith apologised during his evidence for, on reflection, making “decisions at the scene which are obviously wrong”.
Mr Beresford-Smith, who arrived about 10 minutes before the ambulance took Mr Rowley to hospital, said he decided the incident would be treated as a drug overdose from the police perspective.
He also said it was “more than likely” himself who later decided that the police scene would remain, but fire and ambulance service crews would leave the area, the inquiry heard.
The inquiry continues.