財產法益犯罪，古今中外皆可見其蹤影，足見財產之取得，人類是多麼的渴望，甚至於以犯罪之方式取得財產。而財產法益犯罪種類繁多，其中最為嚴重之罪刑，即是擄人勒贖罪。
擄人勒贖，乃近年因大環境之影響，經濟不景氣之下，許多人選擇鋌而走險，犯下綁票案件，以求高額贖款。例如白曉燕撕票案、台南隨機擄人勒贖案；自此以來，擄人勒贖成為人們聞之色變的嚴重罪行。從擄人勒贖罪之條文觀察，立法者更是設下無期徒刑、七年以上有期徒刑之重罰。
學說與實務上對於擄人勒贖與強盜罪之區分爭議，是為本文研究之開端。學說上有所謂｢兩面關係｣與｢三面關係｣之爭，認為擄人勒贖須具備｢三面關係｣之要件，才能成立擄人勒贖罪，反之，如僅有｢兩面關係｣，則僅為強盜而已。而實務上則以｢被擄人是否被擄離原所在地｣之要件，判斷行為人所為之犯罪是為強盜抑或擄人勒贖。此雖為實務穩定之見解，但實際案件之判斷上，尚有改進之空間。會有如此爭議，本文以為，是構成要件之理解有所不足所致。
為明擄人勒贖罪之構成要件內涵，需以構成要件理論之｢指導形象｣，檢視本罪之不法要件，為達此目的，本文從法制史、外國立法例之角度，尋找擄人勒贖罪之罪質，並加以界定本罪之保護法益為何。再經法益保護之觀點，描繪擄人勒贖行為應有之｢形象｣，並按此｢指導形象｣建立本罪之構成要件，以資解決擄人勒贖罪於實務上所生之問題。
Property crimes exist all time. People want to get the property because they desire the wealth very much. Sometimes they get the property by the illegal way. One kind of property crime, The Crime of Kidnapping for Ransom, is an extremely serious offence.
People commit a crime of kidnapping for ransom maybe because the economic depression affected them. For example, Pai Hsiao-yen case, stochastic kidnap for ransom cases in Tainan. From these cases, people of the community fear this offense. Legislators legislate the article that a person who kidnaps another for the purpose to extort ransom shall be sentenced to life imprisonment or imprisonment for no less than seven years.
Theories and practice argue the difference of the kidnappings for ransom and robbery. The dispute is the focal point in this study. Theoretically, the crime of kidnapping for ransom should be composed of three aspects that are impartial constitutive requirements. If there are two aspects, this behavior is robbery. In practices, the behavior is judged as the crime of kidnapping for ransom by the person kidnapped who is moved to another place. This is stable argumentation, but it is improved possibly. This study considers the debate from Tatbestand (constitutive requirement) is insufficiently comprehended.
For the purpose of understanding that constitutive requirement of the crime of kidnapping for ransom, we need to find the Guidance of Image of the crime of kidnapping for ransom of constitutive requirement. This study searches the Crime of Quality from legal histories and foreign legislations, and it determines the kind of the legal interest of the crime of kidnapping for ransom. According to the legal interest of the crime of kidnapping for ransom, this study describes the Guidance of Image, and it could help to rebuild constitutive requirements of this offence. This study hopes to provide the solution to the practical problems.
