The Covid-19 inquiry’s evidence sessions are draining my faith in its value. We were promised a thorough review, shedding light on how the government made key decisions that affected our health, freedoms and economy. At its best, this rigorous evidence collection would be buttressed by examining the outcomes, deriving transferable lessons for better decision making in future civil emergencies. Instead, sessions are getting bogged down in tedious procedural detail and wrangling over text messages and responsibilities.

This week, Rishi Sunak, the prime minister, was questioned following earlier evidence that Angela McLean, now the UK’s chief scientist, had called him “Dr Death” for prioritising the economy over saving lives. Under interrogation, Sunak at one point cited a controversial June 2020 study from Imperial and Manchester academics suggesting that the first lockdown’s costs may have outweighed the value of deaths avoided. His inquisitor, Hugo Keith KC, gave the comment short-shrift, stating “I don’t want to get into Quality Life Assurance models [sic].”

This dismissal of Sunak’s reference to quality-adjusted life years (QALY) analysis — a cornerstone in public health for gauging the cost-effectiveness of interventions — was striking. Here was the former chancellor alluding publicly, for the first time, that even the first lockdown may have been a mistake. Keith’s failure to follow up directly hardly quells fears that the inquiry isn’t much interested in evaluating the full costs and benefits of lockdowns, which, by Sunak’s own admission, the Treasury itself never modelled comprehensively.

Sunak was correct in saying that doing such an analysis, particularly early on, was difficult. The government would have had to model how far the public would have voluntarily locked down anyway to avoid waves of the virus, the inevitable economic downturns this brought, and the uncertain “impacts that would be felt down line” from lost schooling and restricted socialisation. Estimates would have depended on assumptions about future vaccine availability and so whether temporary shutdowns saved lives or simply postponed Covid-19 fatalities. Putting a money value on human lives saved is controversial at the best of times, even if economists like to do it.

Yet while critics dislike these grubby “all-in” value calculations, what alternative is there when aggregating various impacts simultaneously? Sunak admitted that the government’s goal was never simply to suppress the virus to minimise deaths. Later he palmed off the Treasury’s failure to do cost-benefit analyses itself, saying that was a job better suited for the Covid-19 taskforce and Cabinet Office. So was there ever any holistic framework used to make policy decisions, or was everything ad hoc? Keith again failed to grasp the nettle through follow-up questions.

The inquiry to date has thus gone into exhaustive detail on the who, what and when of specific decisions, torturously analysing Matt Hancock’s “diaries” and Dominic Cummings’s WhatsApp messages. But these major omissions in the cross-examinations mean that it is failing to address more fundamental questions: was there any coherent framework for making decisions on policies that entailed such complex trade-offs? And could there have been?

Rishi Sunak was grilled, for example, on why public health officials hadn’t been consulted more in developing the Eat Out to Help Out scheme. However, he was never directly asked how much increased risk of transmission from incentivising dining in restaurants would have made him even rethink the scheme.

With the colossal impact of Covid-19 on every aspect of our lives, any inquiry worth its salt must do more than just provide a historical record. Ideally, it would dissect the thinking — or lack thereof — that lay behind each decision, from lockdowns and hospitality packages to testing and vaccine regulations. Right now, we’re instead watching a very expensive game of political “he said, she said,” that risks delivering little beyond the cathartic benefits of everyone saying their piece.