It was clear the Bichard Inquiry, into how police cleared Ian Huntley to work at a college despite a string of sex allegations, had reached a significant stage.
By Tom Geoghegan
BBC News Online
Thirty journalists packed the inquiry's media room on the fifth floor of a modern office building in High Holborn, watching events next door on a big screen.
Inside what resembled a hi-tech courtroom, Chief Constable Tom Lloyd of Cambridgeshire Police was in the witness seat.
His force had investigated the Soham murders but any satisfaction in putting the culprit behind bars seemed a long way off.
Chief Constable Tom Lloyd admitted failings
What has since emerged is the failings of his force to properly check Huntley's background before allowing him into a position where he met his 10-year-old victims.
Moments after the chief constable began giving evidence at 1030 GMT, the full extent of these errors became clear.
Wearing a full police uniform and taking occasional sips of water, he was watched by Kevin and Nicola Wells, who sat in the front row.
Their daughter Holly was on the front pages of some newspapers following a television interview in which they revealed their determination to rebuild their lives.
This context gave the proceedings an emotional edge they had previously lacked and made the admissions which followed all the more shocking.
First there was the wrong date of birth put in the Child Access database, then the check on the Police National Computer made in the name of Ian Nixon, not Huntley.
Chief Constable Lloyd also admitted it was "more likely than not" that no fax was sent to Humberside Police asking them to check Huntley's background.
The fourth key error was that the Huntley file was closed without checking for a response from Humberside Police.
Inquiry counsel James Eadie was damning in his assessment. He said: "In this one snapshot of one case, there are more or less serious errors at every one of the four basic stages of the process."
He highlighted parts of the force's own internal investigation into the system, in a report previously unreleased.
It concluded the system was designed to cope with volume at the expense of accuracy, and management supervision was "not adequate and in reality non-existent".
Mr Eadie put it to the chief constable that this meant unsuitable people could end up working with children, to which he answered: "Correct".
Behind the jargon about "flow variations", "systemic problems" and "audit trails" there were several candid moments when the chief constable admitted responsibility.
But when pressed by Mr Eadie on why his witness statement only mentioned two errors and ignored several others, he denied a cover-up.
"There was absolutely no intention to cover anything or not disclose anything."
He painted a picture of a vetting team doing the best it could working under intense pressure.
After taking a break, he appeared to be more bullish. He said his team was in fact working to a "high standard" and improvements had been made.
This raised perhaps the most alarming question of all - how many other forces are making the same mistakes?