The Liberal Democratic group leader says his members have taken the “honourable” decision to resign from their posts, although both will remain as councillors.
This comes after it was revealed they were involved in the licensing decision to allow sexual offenders to drive taxis in the city.
The Mayor of Milton Keynes Subhan Shafiq personally vouched for the taxi licence application of a man who had been convicted of a string of sexual offences.
Councillor Stuart Burke, who represents Shenley Brook End, has been Licensing Committee chairman since 2010.
Mr Burke said: “It is with regret that I have decided to resign as Chair of Licensing and Regulation.
“It is clear that on reflection I made an error of judgement in taking the decision to grant a taxi license in this particular case.
“I am pleased that there are now much clearer draft rules on how to deal with applicants that have paid the price for their crime.
“I have enjoyed my last four years as Chair of Licensing & Regulation.
“I would like to thank my fellow committee members and all the council officers who have helped me while I have been Chair. I will continue to work hard for the residents of my ward”
Lib Dem group leader Douglas McCall said: “In light of recent events and new draft regulations regarding the way licensing applications are now processed and how spent sentences are taken into account, two Liberal Democrat members have taken the honourable decision to resign from their current posts.”
Labour Councillor Gladstone McKenzie, who represents Bletchley Park, also left his role on the licensing committee.
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