A descriptive study of the mail bomb offender arrested in the United States from January 1, 1974 to December 31, 1975

Purpose: The objectives of this study were: (1) to attempt to discover identifying characteristics common to the mail bomb offender; (2) to attempt to identify any similarity in the methodology utilized by the offenders; (3) to provide base line data for future research which can be used in the development of prediction models for dealing with mail bomb offenders; and (4) to provide future investigators an insight into the situations which have previously existed that resulted in a mail bomb offense. Methods: The data for this study were obtained from the official records and reports of the United States Postal Inspection Service. Only those cases which resulted in an arrest were included in the study. A total of eighteen cases were included which resulted in the arrest of twenty-six offenders. Data relating to the offender and data relating to the methodology utilized by the offender were compiled as follows: Data Relating to the Offender 1. Age 2. Race 3. Sex 4. Occupational background 5. Educational background 6. Primary motive 7. Motive by age 8. Prior Arrest History by motive 9. Intended victim by motive 10. Height and weight characteristics of male offenders Data Relating to the Methodology of the Offender 1. Month device was mailed 2. Day of week mailed 3. Mailing location in relation to residence of offender and addressee 4. Days elapsed from date of offense to date of arrest 5. Explosive composition of device 6. Number of devices resulting in detonation and injury Findings: Some of the more significant findings from the data studied are as follows: Age – The data suggests that this crime is primarily an act characteristic of younger individuals as the median age is 24 years and the age group of 15 to 29 years represented 69.2 per cent of all arrestees. Race – The crime appears to be characteristic of the Caucasian race as all of the twenty-six arrestees represented in the study were Caucasians. Sex – The crime is primarily a male act, as twenty-two of the twenty-six offenders arrested, or 84.6 per cent were male. Prior Arrest History: The data indicates that the mail bomb offender tends not to have been previously involved in law violation, as only eight, or 31 per cent of the arrestees had previously been arrested. Motive: Three primary motives were identified in the cases in this study: sex, avarice, and revenge. The most likely motive in a mail bomb case is one of sexual interest, which was the primary motive in nine of eighteen cases studied, or 50 per cent of them. Motive of Offender by Age – The data indicate that the older offenders are more likely to be motivated by revenge than any other reason, as five of the six offenders who were over forty years of age were motivated by revenge. No other age categories appear to be highly correlated with motive. Mailing Location in Relation to Residence of Offender and Addressee – The offenders tend to mail from locations in cities other than those in which they or the addressee reside. Only four of the eighteen mailings (22%), were mailed in the city to which they were addressed. Twelve of the mailings, (67%) were made outside the city in which the offender lived.