A Senate committee wants Auditor-General Edward Ouko to scrutinise the Sh63 billion Medical Equipment Services programme and a report tabled in the House in the next 60 days.
Lawmakers want all Cabinet secretaries and principal secretaries who have served in the Ministry of Health since February 2015 to be questioned to ascertain who is responsible for any gaps in the leasing of the equipment and any other improprieties.
Apart from Sicily Kariuki, Transport and Infrastructure Cabinet Secretary James Macharia could be dragged into the matter that has prompted the Council of Governors to complain over the high cost of the equipment, saying county bosses were not involved in the procurement process.
Others who could be roped in are Ms Khadija Kassachoon, Nicholas Muraguri and Peter Tum, who all served at different times as principal secretaries since the equipment contracts were signed in 2015.
The Standing Committee on Health further wants each of the five contracts isolated and a case-by-case analysis of the value for money made.
In a report tabled in the House on Thursday, following last week's meeting between the Senate and Ms Kariuki, the committee indicts the ministry, saying various documents relating to the acquisition of the equipment are missing and that the papers submitted to the House by Ms Kariuki for the probe required further scrutiny.
"It is not clear whether the county governments were involved at the policy formulation stage and conceptualisation of the project. The consultation process took place after the ministry had conceptualised the project," Senator Michael Mbito told the House when he submitted the report.
In particular, the committee wants State investigative agencies to look into the legal basis of the equipment contracts, especially whether the legal requirements of the Constitution under articles 6 (2), 186 and 189 were respected.
"It should be established whether the counties were coerced or entered into the MES arrangements under duress, and if so the legal implications of the contracts and the consequential activities should be established," he said.
Nandi Senator Samson Cherargei said the probe had established there was no needs assessment conducted by counties.
"There was no due diligence and those who are supposed to have carried out the process need to be held responsible and prosecuted," Mr Cherargei, who also chairs the Justice and Legal Committee, said.
He proposed that legal and administrative action be taken against any person who was directly or indirectly involved in the impropriety in the MES contracting and the implementation process.
However, Makueni Senator Mutula Kilonzo Jr expressed dissatisfaction with the report, saying it was weak as it did not address the fundamental challenges facing the equipment as it is silent on the decision to vary the contract yearly.
"It is a fact that the contract has been varied. But the report has not interrogated the variation," he said, noting that the initial contract was for Sh3.8 billion.
But it was later moved to Sh4.5 billion, then to Sh6.1 billion and later Sh9.6bn.
Mr Kilonzo Junior argued that a contract sum cannot be varied and the challenged the committee to declare it as illegal.