A response to an FOI request says that releasing the information would “inhibit officers from providing free and frank advice”.
However, they say the council has carried out a risk assessment in the event of a no deal Brexit and has been told by the Lincolnshire Resilience Form that the county is at “low risk”.
“Disclosure of the information requested would cause a “chilling effect” as it would inhibit the free and frank provision of advice in the future, and that loss of frankness and candour would damage the quality of advice and deliberation and lead to poorer decision making,” said the FOI response.
“The issues surrounding Brexit, particularly in relation to what may happen if the United Kingdom leaves the European Union without a deal, are current and divisive.
“Whilst it is understandable that individuals are interested to know what actions local authorities are taking and what risks there are to the provision of local services, the council must have a “safe space” to enable it to consider sensitive issues and believes that premature public or media involvement would affect the way the council provides its services.”
The request for updated information was made by John Bland, chairman of the Lincolnshire branch of the European Movement, in August.
Mr Bland said he used the same wording as a successful request he made last year.
He has also had a similar refusal from South Holland District Council which pointed him in the direction of the Lincolnshire Resilience Forum.
Mr Bland said: “Given that the county council were happy to release information last year, it begs the question why they are seeking to find every excuse under the sun not to release it now.
“The wording of the response is something that Sir Humphrey would have been proud of.
“The leaders of the local authority have always talked up Brexit as a positive event, yet their own assessments did highlight risks that Brexit would only heighten.”
He disputed the assessment of No Deal Brexit being a low risk for the county.
He pointed to concerns in the reports of his last FOI such as the effect of increased Labour costs, fall in the pound and supermarket competition on the viability of food processing factories in South Lincolnshire.
The decision has also come under attack on Twitter from campaign group Stamford for Europe who accused the council of “hiding” the information.
Justin Brown, assistant director for growth at Lincolnshire County Council, said: “We’re working with our partners to ensure we’re prepared for any eventualities arising from Brexit.
“At this stage, it’s difficult to predict the exact impact on the county, and it would be inappropriate for us to speculate publicly on what the consequences of a no-deal exit might be.
“However, we continue to consider the possible outcomes and how we can make the transition as smooth as possible.”