Dr Giorgini interrupted her. ‘This is all a bit much, Jessica. I have just finished the postmortem and need to speak to the coroner and DCI Anderson first. I shouldn’t discuss the results and my findings until that’s done . . .’
‘I really need to know because we may need to act quickly.’
Nicki sighed, ‘What I tell you is strictly between us for now. OK?’
‘I won’t tell a soul.’
‘I used the hospital’s equipment to check for potassium levels in Johan’s blood and urine. They were dangerously high, and I have concluded that this was the cause of his heart attack. I can’t rule out that he might have been injected with potassium. There were no needle marks in any unusual places, but that’s not tosay he wasn’t injected in the same site as a previous injection to conceal a criminal act.’
‘If his wife Michelle injected potassium in his body, he’d know and would have said something. But it’s highly unlikely a nurse or doctor did it.’
‘I agree, not even accidentally. I have narrowed down the time frame of the sudden increase in his potassium level, which was last checked at eight a.m. this morning and was just above normal.’
‘Johan was on an intravenous drip. Could it have been put in that?’
‘It’s possible, and it would cause a slow feed into his body. I’ll speak with the coroner, then call Anderson and let him know my findings, but I won’t mention we’ve spoken or anything about the drip. I’ll let you do that. As you know, I’ve just started in London and I don’t want to start pissing people off by not following procedure.’
‘Is there any chance you could inform Anderson first in the next few minutes?’ Jessica asked, knowing she was pushing it.
‘You’re like a dog with a bloody bone. I’ll call him now.’
‘Thank you, Nicki. I owe you big time.’
‘Too right you do,’ she laughed, ending the call.
Jessica wanted to run into the station but forced herself to sit in her car for ten minutes before calmly walking in. She intended to speak to Chapman first, but he wasn’t in his office, so she went to see Anderson and saw that Chapman was with him.
‘I thought you were going home,’ Chapman said.
‘I was about to leave, but I thought I’d see if the postmortem results had come in. I also got some interesting information from Guy that I thought you should know about.’
‘That was perfect timing, Jessica. Dr Giorgini hasn’t completed her report yet, but she just called me and said thatJohan De Klerk’s potassium levels in his blood were dangerously high and concluded it was the cause of his heart attack.’
‘Did she say why she thought they might have been so high?’
‘She said someone might have injected him with a fatal dose.’
‘That’s interesting,’ Jessica said, pretending this was news to her. ‘Especially since Guy has uncovered a previous case of potassium poisoning.’
Anderson held a hand up. ‘Before you go any further, I also spoke with Doctor Babu again. He said sudden stress can trigger hyperglycaemia and, in some cases, contribute to an increased risk of heart attack, especially in individuals who have just been through a traumatic incident. If, as we suspect, Johan was lying, his stress levels would have gone up, which, coupled with his injuries, could . . .’
Jessica interrupted him. ‘Michelle De Klerk was a junior barrister on a case involving potassium poisoning, which means she has knowledge of its use and its effects on the human body.’ She had their undivided attention now, as she repeated her conversation with Guy.
‘Bloody hell, this doesn’t look good for her,’ Anderson remarked.
‘It’s unlikely Michelle injected him with the potassium, but she could have put it in his drip bag. I think examining it for fingerprints and DNA needs to be done asap.’
Anderson nodded. ‘Do it.’
‘I can call Taff and Diane and get them to go to the hospital, seize the bag and search Johan’s hospital room for discarded syringes and anything else of evidential value.’
‘Tell them to ask Doctor Babu for permission to do the search,’ Anderson instructed.
‘We’ll need to get Michelle’s fingerprints. Should we do it covertly or ask her?’
‘No need. I got her elimination prints at the hospital when I took Johan’s the day after he was attacked. For now, she doesn’t need to know anything about what we are doing.’
‘I still don’t understand how and when Michelle could have tampered with the drip bag,’ Chapman said.