For new readers and those who request to be “好友 good friends” please read my 公告栏 first

Finger Print vs. DNA Evidence in Solving Crimes

There is a popular program on US cable TV called “Forensic Science” which features real crime solving in each episodes. Typically the story involves murder. In olden days (more than 30 years ago) of detective story, real or fictional, finger prints often play a crucial role. However, finger prints can easily be destroyed or corrupted. Experienced criminal always remember to wipe the crime scene clean. However, since the breaking of the DNA code and advances in the science and technology of DNA testing, some 20+ years ago, DNA evidences have become an alternative to finger prints as individual identification. DNA has many advantages over finger prints. We unconsciously leave such evidence everywhere – blood spots, used drinking cups, smoked cigarettes, shedding skin cell, et al. They are not as easily wiped clean although decoding them require specialized equipment nor do we have a database of DNA samples as we do with finger prints. Thus, identifying a particular DNA sample with a particular human being through blind searching is not possible at this point (on the other hand, comparing one finger print sample with millions of known finger prints in vast databases can be done quickly). Watching the TV program every night should convince everyone that “getting away with a major crime” is very difficult these days!

Notes added 4/16/2019 Never mind survelliance camera is everywhere! And face recognition software are amazingly accurate. Telephone companies know where you are and what you are saying on the phone when you carry your cell phone with you. Only way to defeat this is to remove the battery from  the phone.