Homicidal Poisoning in Japan: Offender and Crime Characteristics
| Author | Wataru Zaitsu |
| DOI | 10.1350/ijps.2010.12.4.191 |
| Published date | 01 December 2010 |
| Date | 01 December 2010 |
| Subject Matter | Article |
Homicidal poisoning in Japan: offender
and crime characteristics
Wataru Zaitsu
Forensic Science Laboratory, Toyama Prefectural Police Headquarters, 1-7 Shin-Sougawa,
Toyama-shi, Toyama 930-8570, Japan. Email: wataru0112csi@yahoo.co.jp
Submitted 28 November 2009; revision submitted 16 March 2010;
accepted 26 April 2010
Keywords: Japanese homicidal poisoning, instrumental, expressive,
profiling
Wataru Zaitsu
is Chief of the Forensic Science
Laboratory at the Toyama Prefectural Police
Headquarters, in Japan.
A
BSTRACT
The purpose of this study was to examine
empirically those who committed homicidal poi-
soning in Japan (N = 96). Typically, offenders
were middle-aged (mean 43.2 years), had a fixed
residence (99 per cent), had no criminal record
(81 per cent), were employed (68 per cent), and
married (56 per cent): 54 per cent of the
offenders were female. The offenders could be
differentiated by categorical principal component
analysis (CATPCA) into two poisoning themes:
‘instrumental’ (N = 65) and ‘expressive’ (N =
31). In ‘instrumental’ poisoning, the offenders
were likely to induce a coma in a victim using
medical supplies such as hypnotics, and then
murder the victim, usually by strangling or
stabbing. There were more co-offenders among
‘instrumental’ poisoners than among ‘expressive’
poisoners. The offenders who committed ‘express-
ive’ poisoning were inclined to poison victims
serially or collectively in the workplace during
daytime. These offenders were more likely to live
with a parent/parents and exhibit mental
health problems than those who committed
‘instrumental’ poisoning.
INTRODUCTION
The number of victims of homicidal poi-
soning in the United States has ranged from
eight in 2000 to ten in 2007 (US Depart-
ment of Justice, 2004, 2007). This number
is relatively low compared with other types
of homicide (approximately 0.0008 per cent
in total homicides). In Japan, according to
Nishimura (1999), murders related to poi-
son constituted 0.5 per cent (13 cases) of
the total number of homicides from 1973 to
1992.
Although homicidal poisoning is quite
rare, there have been several sensational
crimes in the last 20 years in Japan. For
example, in 1995, members of the religious
group AUM Shinrikyo distributed lethal
poison gas (sarin, a nerve gas) in subway
trains (‘Nerve gas’, n.d.). Nishida (2001)
interviewed four AUM members who were
prosecuted for this attack as well as 76
former members of the group, and con-
cluded that the AUM members had obeyed
their guru completely and had been psy-
chologically manipulated by him. Another
example is that of a high-school girl who
was inspired by Graham Frederick Young, a
British famous poisoner. She investigated
the effects of poison on her mother by
intermittently lacing her mother’s food with
thallium (‘Schoolgirl blogger’, 2005). In
Page 503
International Journal of Police
Science and Management,
Vol. 12 No. 4, 2010, pp. 503–515.
DOI: 10.1350/ijps.2010.12.4.191
International Journal of Police Science & Management Volume 12 Number 4
To continue reading
Request your trial