In a Brexit select committee hearing this morning, Davis said that the government had not published impact assessments - which had been demanded by a vote in Parliament - because they did not exist in the sector-by-sector form that MPs assumed.
The U.K. official shepherding Britain's departure from the European Union says no formal assessments have been made on the economic impact of leaving the 28-nation bloc.
He said the government had produced a "sectoral analysis" of different industries but not a "forecast" of what would happen when the United Kingdom leaves the EU.
DAVID DAVIS today admitted that some of the reports produced by his department "weren't that good" and insisted it was impossible to predict the impact of Brexit.
Mr Davis told the committee: "You don't need to do a formal impact assessment to understand that, if there is a regulatory hurdle between your producers and a market, there will be an impact".
"Not that I'm aware of, no".
He added that in this such circumstances any assessment of the potential impact of the change on various sectors of British industry using existing economic models would not necessarily be "informative".
And in October, he told the Brexit committee that Prime Minister Theresa May had read "summary outcomes" of impact assessments, which he said went into "excruciating detail". However he reiterated that publishing a series of sectoral impact studies would undermine the UK's negotiating position and potentially reveal sensitive information.
"No", Davis replied, explaining that such models were "not as straightforward as people imagine" due to the many variables.
Benn asked: "Just to be clear, has the government undertaken any impact assessments on the impact of leaving the European Union for different sectors?"
"Similarly, what we are dealing with here in every outcome - whether it is a free trade agreement, whether it is a WTO outcome or whether it is something between that on the spectrum - it is a paradigm change". The Queen famously asked why did we not know.
Lib Dem committee member Wera Hobhouse accused Davis of "misleading Parliament" over the studies.
Davis replied that there was no assessment on a "sector-by-sector basis".