Forensic Chemistry Flashcards
The art or study of formal debate; argumentation
Forensics
The use of science and technology to investigate and establish facts in criminal or civil courts of law.
Forensic Science
The branch of science which deals with the study of matter, the changes it undergoes and the energy that accompany these changes.
Chemistry
The branch of Chemistry that deals with the application of Chemical theories and principles in the solution of legal problems in connection with the administration of justice.
Forensic Chemistry
Forensic Laboratories in the Philippines
PNP Crime Laboratory
PDEA
NBI Crime Laboratory
Functions of Chemiatry
- Conduct Qualitative and Quantitative Examination of Dangerous Drugs as well as volatile substances.
- Conduct examination of explosives and/or explosive ingredients.
- Conduct examination of Firearms and Paraffin casts for the presence of Gunpowder Nitrates.
- Conduct Gunpowder examination for clothing for possible gunshot range.
- Conduct Chemical-Toxicological examination of human internal organs, gastric contents, blood water and food sample and other substances.
- Conduct examination of fake products in case of unfair trade competition.
- Conduct blood alcohol determination.
- Examine urine and other body fluids for the presence of dangerous drugs.
- Conduct researches related to the cases being examined.
- Give lectures on Forensic Chemistry & Toxicology to Police/ Military training centers, investigative units, various schools and universities.
- Testify and give expert opinion in court.
- Respond to queries of all investigative units and render expert’s opinion regarding matters related to the application of chemical principles for the purpose of assisting investigators in developing investigative leads.
- Conduct Field laboratory work and clandestine laboratory investigation.
- Perform all other official duties assigned by the Director of PNPCL and his duly authorized representatives..
Four Stages in the Practice of Forensic Chemistry
- Collection and reception of specimen –
- Actual examination.
- Report writing of the result of examination.
- Court appearance
is the proper taking, handling and packaging of specimen.
Collection
is the process of receiving the specimen by entering the condition of the sample in a log book.
Reception
Consideration in reception of sample
i. Sufficiency of sample(s)
ii. Standard for comparison
iii. Maintenance of individuality –
iv. Label and seal
all evidences should be separately wrapped to avoid contamination.
Maintenance of individuality
use for proper identification in court presentation and to avoid possibility of tampering evidences.
Label and seal
Labels should include:
the case number
name of collector
nature and source of sample date and time of collection.
Specimens brought to CL must be accompanied by a request for laboratory examination
- Addressed to D, PNPCL. Attention: C, Chemistry Div
- Nature of Case
- Specify lab exam request
- Description of the specimen.
Two Type of Examination in Forensic Chemistry
Qualitative Examination
Quantitative Examination
identification of substance present in the sample.
Qualitative examination –
determining the percent purity of the sample.
Quantitative examination –
Steps in Qualitative Exam
Physical test
Chemical (color) test.
Confirmatory test
Describing, weighing, microscopic exam
Physical Test
Simons test, Marquis test etc.
Chemical (color) test
Chromatography & Spectroscopy
Confirmatory Test
any chemical compound or mixture that, under the influence of heat, pressure, friction or shock, undergoes a sudden chemical change or decomposition
Explosives
Classification of Explosives
A.According to the velocity of reaction involved
B.According to their chemical structure
C.According to their application or design
According to velocity of reaction involved
A. High Explosives
B. Low Explosives