As violent crimes such as robbery, rape, and arson, which is the factor not only cause serious damage to victims economically, psychologically, and socially but also increase the fear of crime to the ordinary person, continuous, systematic research and the preparation of measure are needed. The measure against violent crimes might be achieved in several ways, but the best solution is to reduce the violent crime occurrence. In Particular, serial violent crimes have more significant criminal policy meaning rather than general violent crimes based on the continuity and intensity of crime.

A. Research method

1. Record investigation

The research data was collected through record investigation and interview survey. The record investigation was conducted by taking ten-year arson record through the cooperation of supreme prosecutor's office, predicting the serial events, and applying for reading the case record to the district public prosecutor's office. On the other hand, as the analysis of nonserial arsonist is simultaneously completed to understand and analyze the character of serial arsonist, nonserial arson incident was randomly selected from the other incident list excludes the serial incidents by considering occurrence year, district public prosecutor's office, and the name of a crime which are regarded as serial case. As a result of record survey, 410 cases records were investigated exempt from the case records are discarded because retention period was passed and transferred to the other district public prosecutor's office.

2. Interview survey

The accommodation condition of forty-one prisoners who are regarded as serial arsonist are understood and the possibility of interview is checked with the cooperation of correctional facility. Twenty-two prisoners are agreed with the interview and interview survey was conducted. Individual interview was carried out at the proper places such as counseling office, reception room, and conference room based on the situation of correctional facility by carrying a semi-structured questionnaire. Interview was implemented under the attendance of staffs and research assistant entered the interview contents into the computer. The interview hour is from about one hour to two hours and ten minutes and average hour is approximately one hour and thirty minutes.

B. Research result

1. The general character of serial arsonist

The character of serial arsonist is that male get an absolute majority, the percentage of under 30 years is about over 60%, their education level is low because the percentage of the uneducated to people who are not graduated from middle school is over 40% according to the record survey. Furthermore, they are normal unmarried people who have no physical disability, mental disease, and mental disorder and work as a labor worker who live with their parents. Although the percentage biological parents raise is over 50%, over half of them is their family relationship is bad, and the percentage of child abuse and runaway is approximately 10% according to childhood experience. In addition, the percentage of person who has a different kind of criminal record is over 60% and the percentage of people who previously convicted more than four crimes is highest among them based on their criminal record. In contrast, the percent of people who have the same kind of criminal record like arson among them is just 13%. This character of serial arsonist is shown through interview survey, and they live in poor surroundings. As they are unemployed person, and work as a labor worker or low pay unskilled labor, they are suffered from economic difficulties when committing crimes. Most of they are unmarried, divorced, have no friends, and formal relationship with the other people, and their social supporting system is very weak. Their stress solutions are drinking and independent activity even if they relieve stress through the other methods. They had deprived childhood and the cases that they are raised by grandparents or single parent and grown up in the neglected family environment were founded. They grew up under strict father and ran away for the lack of love. Moreover, they did not enter a upper school and dropped out of school due to family reason. They are also victim or attacker of violence throughout the school years. The remarkable character of personality is the lack of controling their feeling and they are introverted or timid. Short-tempered people express their anger by combining introverted side, but they did not express their feeling. They drink alone and violent personality was expressed because of their drinking habits.

2. The Character of serial arson incident

The character of arson incident is that most of they committed crimes by themselves after drinking with the lighter that they carry without any plan at dawn according to record investigation. The target of crime is that indoor case (50.6%) is slightly more than outdoor case (49.4%). For example, outdoor target is wastebasket, thrown thing, vehicle, banner, placard and so on, and indoor is public facility such as dwelling, shopping mall, shop, and toilet. As the distance of occurrence place is within 2km from suspect's house is 70%, and the distance between the occurrence place is 90%, they walk to the familiar places. The case of leaving the place with carrying crime tools after committing crimes is 70%. Over half of crimes is their intent is to express anger such as personal resentment, pessimism of circumstance, social inferiority and the case from mental disease or mental disorder is 15.6%. Especially, the differences between serial and nonserial incidents are clearly shown in the occurrence time, target is indoor or outdoor, the familiarity of occurrence place, means of transportation, the distance from criminal's house, drinking or not, and action, and level of regret after committing crime. That is to say, the percent of occurring at dawn is much more higher than, the case of not drinking is more than, the case that occurrence place is more close to suspect's house, familiar, outdoor is relatively more than, the case of walking to the place after is more than, and the percent of immediately leaving the place is higher than the nonserial incident in the case of serial incident. The case that serial arsonist regret about their crime is more than nonserial incident.
The detailed approach of serial incident is possible through interview survey and it was mostly occurred near the house or familiar place at time from night to dawn. They walked the places from the bar or the case that moving time is about five minutes is the highest. This means that they select the occurrence place within the living radius. The intent of arson is classified the one caused by anger and by impulse, and the anger is the one is toward specific object as well as their circumstance. The anger toward specific object is caused because the victim causes financial loss and emotional insult and their circumstance is caused by the accumulation of abstract stress. Impulsive arson is occurred by mental disease and desire for stimulation. Anger and impulse are not unrelated factor, but stress about their circumstance trigger the desire for arson. They are under various stress and maintain their life in a state of tension. This stress factors are connected to arson in many ways. The stress that they suffer from is result from economic difficult such as poverty, and unemployment, emotional difficult such as family trouble and love affair, and other difficulty. The deciding time of crime is various situation such as conflict situation that is motivation factor is broken out, drinking after conflicting, everyday drinking, and the case of having a desire for arson regardless of confliction or drinking is shown. Most of they drank before committing crime, and the case of moving to the house or other place in the middle of catching fire is relatively more than the case of running away from the place after confirming burn down. CCTV is greatly contributes to the arrest of arsonist, and CCTV has the crucial role in over half of cases which are surveyed. However, as some criminals look carefully whether CCTV is installed or not and commit crime by avoiding the surveillance range of CCTV, the development of diverse investigation technique is necessary rather than dependence on CCTV. Also, there are many cases from the report of victim or witness. Some arsonists are interested in or satisfied with catching fire, but feel displeasure or afraid about it. The interesting thing is the fear they feel plays the role as stimulation provides thrill. The case that they are not concerned about the punishment and arrest because they think that arson is not serious crime, but they do not think about subsequent event as they are absorbed in action itself, and they have no sense of guilty.

3. The typical character of serial arson incident

This research define the case of occurring the arson more than second times at different places and classify the 'spree arson' which is continuously occurred for one day without any psychological cooling-down period, and 'serial arson' is broken out with over one day psychological cooling-down period. This is how the relevant character between the arsonist and arson incident is different whether psychological cooling-down period is or not in understanding the serial arson. This analysis process is used as basic data for the suggestion of standardized concept on the serial incident in discussing about serial crime in the future. The typical character of serial arson incident is as follows.
First, this is the result about the personal character of serial arsonist. The age group of arsonist is under thirty group is over 70% in the case of serial arson, and about 50% in spree arson. The age of serial arsonist is lower than spree arsonist. In particular, serial arson by teenager and young people is happened a lot and reach to a serious level according to high percentage of teenage and twenties age group. As serial arsonist had more experience of children abuse and runaway compared to spree arsonist, intensive debate about the relation between the experience in family and society and serial arson is necessary.
Second, the character is shown in the dealing process and result of serial arson. It takes longer time to arrest the suspect in the serial arson incident rather than spree arson, our anxiety and sense of crisis expected to be lasted for a long time. The percent of final decision in the first trial is over 50% and much more than spree arson.
Third, this is the character of serial arson incident. The percent of committing crime after drinking in the spree arson is more than the serial arson, the rate of escaping after committing crime in spree arson is lower and the percent of regretting is relatively higher compared to serial. In other words, most suspect of spree arson commit crime after drinking at dawn and regret about their action.
In conclusion, there is little difference in the person character or crime record based on the type of serial arson, but it is necessary to survey the incident on the classification of spree arson and serial arson whether psychological cooling-down period is or not in order to understand the serial arson. As a result, diverse debate on the measurement standard of psychological cooling-down period will be progressed in the research of serial arson.

4. The improvement plan of arson investigation system

The biggest problem is lack of civil fire investigation system and cooperation system like information sharing between fire investigation agencies. To develop the weak civil fire investigation area compared to the Western countries, fire investigation education which public area monopolize is activated in civil area, fairly conduct the fire investigator qualification examination at the third-party organization, the legislation of civil investigator that is currently at a standstill is urgent for the institutionalization of civil fire investigation business. Fire investigation education will be conducted, the personal exchange is activated through the academy and seminar, and regulation, which both organizations' responsibility sharing such as task force team construction and relevant information sharing is specified, is made and implemented for the establishment of the cooperation system on the fire investigation between the police and fire authorities.
Positive attitude of public education institution that fire investigation education is carried out and integration of fire investigation organization is desirable to develop the ability of fire investigator. Furthermore, The raise of Fire Research Laboratory in National Forensic Service to the department and Fire Scientific Laboratory belong to Fire Academy to Fire Scientific Research Center which is managed at the form of the civil organization is worth considering to deal with increasing fire investigation work like the investigation case of fire remnant.