Documents submitted to the Bichard Inquiry last week showed that the upgrade programme left the force with intelligence systems that were still inadequate and a source of frustration two years after the project's completion.
The revelations follow disclosures by Humberside's chief constable David Westwood that Humberside Police had been forced to delete intelligence data on Huntley to comply with the Data Protection Act.
An intelligence systems review by detective superintendent Keith Hunter in October 2002 released to the inquiry revealed that the replacement intelligence system, dubbed CIS2, was "hasty, under-researched and under-funded".
Its introduction led to the loss of "a huge amount of potentially important intelligence and information" and had lost the confidence of the user community two years after its installation.
The net result, according to the report, was that the force had a database that "did not nearly meet user requirements" and "did not fulfil its role as the central, reliable storehouse of all available intelligence".
The report revealed that Humberside Police had no mechanism for collating the intelligence held about individuals on its 26 databases, without trawling each one individually.
The report casts doubt on the ability of Humberside Police to comply with the Data Protection Act. There were no written policies for entry or weeding of data on a significant number of the databases - an omission that Hunter described as "indefensible".
"The inability to ascertain what information we may once have held and what information we may have passed on when the murder suspect was vetted could have led to some damaging publicity," said Hunter.
"More serious was the possibility that the systems operated by this police force could have contributed to a situation in which the suspect was allowed to take up the position of caretaker at the school were he worked."