Carol Mills, who was fired from her position of head of the Department of Parliamentary Services last week, was found by the finance and public administration committee to have presided over an organisation that was "deeply dysfunctional".

In addition to the use of internal surveillance footage, Ms Mills was also criticised by the committee for failing to satisfactorily explain why a $30,000 photography contract was awarded to a person known to Ms Mills.

The committee, chaired by Liberal Senator Cory Bernardi, chastised Ms Mills for failing to declare she knew the photographer until she was questioned about it during committee hearings.

The committee concluded that although there was no evidence of wrongdoing the  chain of events did "not reassure the committee that [the Department of Parliamentary Services] is developing a strong culture of probity and accountability".

The saga has provided a glimpse into the alternate parallel universe of Parliament House - the politics played by the people who run the building as opposed to the politics practised by the people elected to sit on its benches.

The investigation into the department has been running for three years and has exposed the rivalry between Ms Mills, a former senior NSW bureaucrat, and the person who runs the Department of the Senate, Rosemary Laing.

Dr Laing gave evidence more than once which directly contradicted Ms Mills and which the committee relied on for its adverse findings.

The rivalry between the two was so bitter that when Ms Mills was considered as a replacement for the clerk of Britain's House of Commons, Dr Laing emailed British officials outlining why Ms Mills would be an "embarrassing" appointment.

Ms Mills will be given a further chance to explain herself to the committee in June.

But Senator Bernardi warned the committee could not consider her a reliable witness after her previous evidence was found to be "implausible".

Ms Mills could not be contacted for comment.

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