[7] In December 1997, Mallon was one of sixty-one police officers suspended from duty amid allegations of misconduct as part of Operation Lancet.
[7][9] Charges against Mallon included nine of neglect of duty, three of falsehood and prevarication, one of discreditable conduct and one of misconduct towards of a member of the police force, which he described as "minor" disciplinary matters.
[10] By June 2000, the Crown Prosecution Service had found insufficient evidence to bring criminal charges against any of the officers involved.
[6][15][16] He accepted applications for roles in his nine-member cabinet from all parties, though the Labour group on the council initially maintained a boycott.
[3][9] He increased the use of CCTV in the town centre and started a programme of neighbourhood wardens that brought street offences to a historic low.
[15][18] Many residents in Gresham, near central Middlesbrough, including ward councillor and former council leader Ken Walker, vocally opposed Mallon-supported 2005 plans to demolish 1,453 homes across thirty-seven streets as part of a regeneration scheme.
[23][24] The Standards Board for England found that he had brought the office into disrepute and failed to declare an interest regarding his friendship with Bashir on two occasions.
The sale was criticised at the time as undervalued, with independent councillor Len Junier suggesting the deal made had been "dodgy".
[28] After leaving the position of Mayor of Middlesbrough, Mallon took up a role as a non-executive director for a project to redevelop the site of Manston Airport in Kent.
[35] In 2011, Mallon criticised cuts to local government as "a financial war on us" disproportionally affecting more deprived areas, while supporting deficit reduction in principle.