Lawyer Willie Kimani autopsy result and that of the other two people who vanished along with him shows they died from fractures caused by a blunt object.
The autopsy report was conducted at Kenyatta National Hospital by government pathologist Johansen Oduor alongside other specialists and was released on Monday.
According to the postmortem report the three subsequent death occurred as a result of being smashed in the head.
The attackers tied Kimani up, then beat him up several times at the back of his head before suffocating them to death, Lawyer Willie Kimani autopsy result shows. His body was still tied up with a robe when it was found.
The taxi driver however was first choked to unconsciousness and then beaten on the head with the same object. The results indicated that Mwenda suffered a good number of bleeding injuries on the neck, chest and a fracture on his head.
Three Police officers including Fredrick Leliman, Stephen Chebulet and Silvia Wanjiku were seized and kept in custody for the killings of the three men.
Kimani, 32, his client Josephat Mwenda and taxi driver Joseph Muiruri were murdered after they were kidnapped. Their bodies were found dumped in Oldonyo Sabuk river. The two, as well as Muiruri, were found on Thursday last week.
The killing is said to have been caused by the case Kimani was pursuing concerning police brutality in April.
Police in a bid to revenge the alleged lawsuit, charged Mwenda with a range of offenses, including possessing drugs, gambling in public and resisting arrest, rights activists said.
Moments after their floating bodies were discovered, LSK marched to the Inspector General’s office to demand an investigation.
On Monday, about 34 local and international human rights groups and lawyers protested against the killing, calling on government to make the suspects face the law.
The Monday’s countrywide demonstrations took place at Freedom Corner Nairobi, at the Mombasa law courts, the Jomo Kenyatta Sports Ground in Kisumu, and Railways Grounds Nakuru.
The protesters told the IG Joseph Boinnet to clarify whether the AP officer accused of shooting Mwenda in April 2015 is among those detained.
Rights groups have in the past accused some sections of the police of involvement in extrajudicial killings, a charge that the security authorities have denied.
Following the emergence of the Willie Kimani autopsy result, Members of the Thika Law Socitey of Kenya chapter claim they can no longer trust the police. As such the group said they will apply for guns as that will be the only way they can protect themselves against rogue officers.
They met Thika West deputy county commissioner Tom Anjere at his office yesterday to air their views on their plans to defend themselves.