Public figures are at increased risk of attracting unwanted attention in the form of intrusions, stalking and, occasionally, attack. Whereas the potential threat to the British Royal Family from terrorists and organized groups is clearly defined, there is a dearth of knowledge about that from individual harassers and stalkers. This paper reports findings from the first systematic study of this group.

A retrospective study was conducted of a randomly selected stratified sample (n=275) of 8001 files compiled by the Metropolitan Police Service's Royalty Protection Unit over 15 years on inappropriate communications or approaches to members of the British Royal Family. Cases were split into behavioural types. Evidence of major mental illness was recorded from the files. Cases were classified according to a motivational typology. An analysis was undertaken of associations between motivation, type of behaviour and mental illness.

Of the study sample, 83.6% were suffering from serious mental illness. Different forms of behaviour were associated with different patterns of symptomatology. Cases could be separated into eight motivational groups, which also showed significant differences in mental state. Marked differences in the intrusiveness of behaviour were found between motivational groups.

The high prevalence of mental illness indicates the relevance of psychiatric intervention. This would serve the health interests of psychotic individuals and alleviate protection concerns without the necessity of attempting large numbers of individual risk predictions. The finding that some motivations are more likely to drive intrusive behaviours than others may help focus both health and protection interventions.