They have demanded to know what the data will be used for and whether No 10 will be breaching data protection rights if people have not given permission for their information to be collected.
Ian Lucas, a Labour member of the media committee, said the controversy involved the “same individuals” – the prime minister and his now-chief aide – who were at the forefront of the Vote Leave data scandal.
It emerged earlier this week that Downing Street has ordered departments to centralise the gathering and analysis of user information from the gov.uk website ahead of Brexit.
The government insisted the move is simply intended to improve the service and that no personal details will be collected.
But a leaked memo revealed that Mr Johnson specifically linked the gathering of the data to government decision-making over Brexit.
Seen by the Buzzfeed website, the memo said the “XO” cabinet committee in charge of no-deal Brexit preparations had been asked to ensure gov.uk “is serving as a platform to allow targeted and personalised information to be gathered, analysed and fed back actively to support key decision making – in effect, focused on generating the highest-quality analytics and performance data to support exit preparations”.
Nine days later, Mr Cummings – who was found in contempt of parliament for refusing to answer questions about Vote Leave’s law-breaking during the 2016 referendum – emailed officials to stress this was a “top priority”, Buzzfeed said.
In his letter to Ms Denham, Tom Brake, the Lib Dem Brexit spokesperson, wrote: “I would like to clarify what such data may be used for?”
Mr Brake asked if it was proper for data to be “fed back actively to support key decision-making, if the individuals had not granted permission for it to be used in that way”.
And he added: “If such permission had not been granted and data was fed back in this way, would this be a breach of their rights and data protection?
“Will you be seeking to meet with No 10 and the cabinet office to confirm any such data transfer or analysis is within the law and, in particular, that the data will not be used by government to promote their political agenda or be exported to third party organisations such as the Conservative Party?”
However, a government spokesperson insisted: “Across the industry, it is normal for organisations to look at how their websites are used to make sure they provide the best possible service.
“No personal data is collected at any point during the process, and all activity is fully compliant with our legal and ethical obligations.”
Officials said the only change would see the anonymised user data currently collected by individual departments collated across the gov.uk website, generating better information on how the site is used as a whole.
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