This episode was scheduled for broadcast in the UK on 20 September 2001 but was withheld until 1 November 2004 because of the terrorist attacks on the USA of 11 September 2001 and the collapse of the World Trade Center towers. It was broadcast on digital-only channel ITV3 and so was not available to viewers who only have analogue televisions.
When Rebus cracks the password on Brian's computer and is browsing a spreadsheet, many of the names match those of the programme's production staff.
The latin phrase referred to in the plot summary should correctly read 'Nemo me impune lacessit' - 'No one provokes me with impunity' . It is the national motto of the Kingdom of Scotland.