There is no suggestion of impropriety involving any construction companies.
Andrew Manley joined the DIO as its inaugural chief executive in 2011 from the Shell oil company.
A tabloid newspaper reported last month on how he had racked up an expenses claim of £13,743, including £5,542 from 47 nights at a Sutton Coldfield hotel close to DIO headquarters.
The internal investigation will consider whether Mr Manley’s hotel bills, averaging less than £120 a night, actually represented a significant saving on the relocation costs that the taxpayer would otherwise have been expected to pick up for Mr Manley to move to the West Midlands from his Surrey home.
A second tabloid newspaper today suggested that the investigation might also embroil his chief of staff, apparently on the basis that her hair is blonde.
DIO manages £21bn worth of assets and has a £3.3bn annual budget, making it an equivalent size to a FTSE top 30 company. It has 4,900 employees and maintains 45,000 buildings, 50,000 homes for service families and 135,000 single living bed spaces.
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