Television journalist Jacque Maribe and her fiancé Joseph Irungu return to court today to take pleas in a case in which they are charged with the murder of Ms Monica Kimani in Nairobi four weeks ago, with detectives still puzzling over certain aspects of a crime they describe as having been carried out by a "highly trained killer".
They are, for example, wondering why Ms Kimani did not struggle as her hands were tied behind her back and her mouth taped shut.
"Her body did not have injuries consistent with a big struggle against an assailant," a Nation source conversant with the investigation, but who comments anonymously on ongoing investigations, said last evening.
There were also no signs of struggle in the apartment, as one would expect. The source's reading of the scene of crime, he said, indicated that Ms Kimani was tied up "like a goat".
"We know they had been taking wine," the source noted, and wondered: "Was she drugged?"
Police do not think she was tied in the bathroom, the source added, speculating that she might have been trussed up in the bedroom and taken to the bathroom and killed.
The drugging angle would be consistent with the profile of the killer that the police have: A meticulous planner and trained killer who thought about the crime seriously in advance and covered his tracks, including disguising himself in a kanzu and stealing an identity card for use in getting into Ms Kimani's apartment.
Assuming that the killer acted alone and was known and trusted by the victim, then the most likely explanation for the lack of a struggle is that he either tricked her to allow herself to be tied, or just drugged her.
A team of detectives is still in South Sudan going over Ms Kimani's business activities and her alleged relationship with Lt-General Daniel Awett Akot, the deputy speaker of the South Sudanese Parliament and adviser to President Salva Kiir, to see whether the motive for her killing lay there. "The enquiries in Sudan are going to take some time," the Nation source said.
Detectives said they were still trying to conclusively figure out the motive of the murder, and that DNA results were still being analysed.
Reached for comment yesterday, Director of Criminal Investigations George Kinoti would only say that his team had made progress. "We have achieved our threshold," he said in a brief telephone call with the Nation.
Ms Maribe and Mr Irungu appeared before Justice Jessie Lesiit in a Nairobi court last week but could not plead to the charge because Ms Maribe was yet to undergo a mental assessment. She, like Mr Irungu, has since been found fit to stand trial.
An investigator said circumstantial evidence and fingerprints dusted from Ms Kimani's home, wine glasses and furniture have shown that Mr Irungu was in Ms Kimani's Lamuria Gardens flat, quite probably on the night of September 19. However, the forensics team has not given the DNA results yet.
"It will take time before we can really ascertain the biological identity of the killer," said a detective, who is privy to the investigation. "We are relying on circumstantial evidence for now, but we have not been successful in getting any important information from the main suspect in our custody. He has not helped much. All he says is that he was not involved in the murder. He is very guarded."
For now, the source said, detectives have not been able to conclusively establish where Mr Irungu's main residence or central place of operation. The house believed to have been his previous residence in Nairobi's Buru Buru Phase 2 estate is currently occupied by another man.
The murder weapon used to slit Ms Kimani's throat has also not been found.
Last week, Justice Lesiit allowed the request from the Assistant Director of Public Prosecutions Catherine Mwaniki to give detectives a week to tie up their case. Ms Maribe was remanded at Lang'ata Women's Prison while her boyfriend was sent to Nairobi Industrial Area Remand Prison.
Lawyers Katwa Kigen and Cliff Ombeta, for Ms Maribe and Mr Irungu, respectively, protested that their clients had been in custody long enough.
Mr Brian Kassaine, the suspect-turned-State witness who is their neighbour, was released last week but ordered by a Kiambu court to be reporting to the police on a weekly basis.
Reporting by Sam Kiplagat, Stella Cherono and Mutuma Mathiu