Physical Identification Laboratory

Physical identification Laboratory

The main missions of physical identification section are voice identification, firearms identification, and polygraph examination. Recently, there are about 1,200 cases, approximate 3,000 samples, implemented every year.

 

1. Voice identification:

According to the principle of acoustics and acoustic fingerprinting and characteristic reproducibility of peoples’ pronunciation, voice can be taken as scientific evidences for distinguishing the identity.

The recorded evidences may be retained in the process of illegal cases such as kidnapping and blackmail, corruption and malpractice, deception, interference with marriage and the family, slander, election through bribery, drugs trade, etc. These samples may be analyzed and compared by facilities with Spectrogram Software to determine the speaker's identity. In addition, the noise signal of recorded evidences may be reduced and the speaker's voice may be enhanced by the software to make the talking content more recognizable. It can offer the clues to discover the details of the criminal case, and it may also be considered as judicial evidences for the court.

Instrument: Voiceprint recognition screen system, Delta electronics Inc. Application：Speaker verification screen
Instrument: Voiceprint recognition system, MJIB Application：Comparison of normalized spectrograms for further peaker verification
Instrument：Noise reduction software Application：Eliminating unwanted noise within a sound, such as a background hiss, a power hum, or random interference

2. Firearms identification:

Tool machines may produce different consumptions that were worn and torn through time; firearms produced by these tool machines also produced all sorts of different changes as the ones that wear and tear, these changes make the differences among the individual are considered as bases for the comparison and identification of the head of a bullet and shell.

Instrument: bullet collect box Application：In firearm examination, collect the bullet for comparison of traces on fired ammunition

 

 

Instrument：Ballistic speed measurement system Application：Measurement of ballistic speed for wounding capability computation
Instrument：Auto-fired machine Application：Hold the gun and auto-pull the trigger

 

Instrument：Bullet disassemble instrument Application：Disassemble bullets for analysis the contents

 

3. Polygraph examination

    The essence of polygraph examinations is to use the polygraph to record physiological reaction curves such as breath, pulse and skin electricity of the persons who are examined, and then according to the polygraph recordings examiners who has been professionally trained determine whether the examinees tell a lie or not.

The standard operation procedure of polygraph examinations of MJIB (Investigation Bureau, Ministry of Justice, R. O. C.) pursues in accordance with APA (American Polygraph Association) Standard of Practice. It is the position of the APA that a polygraph examination has a high degree of accuracy in detecting truthfulness or deception. Part faculty of polygraph examiners in MJIB achieves the supreme grade membership of APA (American Polygraph Association). The application of the technology of polygraph examination is to judge whether the suspect's statement is true. It will help the promotion and protection of human rights.

 

 

Professional polygraph examination laboratory in MJIB

 

 

 

Instrument: LX4000 Polygraph System, Lafayette, USA.

Pneumo

Cardio

Galvanic Skin Response

During a polygraph examination, the LX4000 computer polygraph system records, stores and analyzes physiological changes of examinee.

4. Image Forgery Identification:
Based on the provisions of The Code of Criminal Procedure and requests of law enforcement agencies in Taiwan, this laboratory administers image analysis and identification cases entrusted from various levels of judicial organizations. The scopes of analysis and identification involve face recognition and comparison (prints and digital images), monitored videotape image restoration, and image enhancement. These image samples came from the crime scenes, traffic monitored records, ATM systems and the films or videotapes are protected under copyright acts. There are approximately 80 cases have to be analyzed each year. Recently, this laboratory makes efforts in improving the quality of image analysis and identification through establishing face image databases, enlarging image analytical instruments and focusing on advanced studies.