Forensic Science and Physical Evidence Questions and Answers

Answer: B

It was the Lafarge Case.

In 1840 Marie Lafarge was tried in France for poisoning her husband with arsenic. The prosecution's first chemical tests were inconclusive, and Mathieu Orfila, the founder of forensic toxicology, was called in; using the Marsh test he showed arsenic in the exhumed body. The defence brought in the chemist Francois-Vincent Raspail to challenge the scientific evidence, which made it the first case in which the defence tried to rebut the state's scientific proof. Marie Lafarge was convicted.

Ruxton's case (1935), the Sam Sheppard case (1954) and the JonBenet Ramsey case (1996) all came much later.

Answer: C

The scene is secured to stop unauthorized personnel from entering the crime scene and destroying the evidence.

Physical evidence at a scene is fragile: footprints, fingerprints, trace fibres and biological stains can be destroyed or contaminated by anyone walking through. By Locard's exchange principle every person who enters both leaves and removes material. Cordoning off the scene and logging everyone who enters preserves the evidence in its original condition and protects its integrity in court.

Police and experts still enter, under control, so stopping police is wrong. Evidence does not escape, and arresting the suspect is a separate investigative task, not the purpose of securing the scene.

Answer: B

The correct sequence is Protection, Recognition, Documentation, Collection and Packaging of evidence.

The scene is first protected, so nothing is lost or added. The investigator then recognises what is evidence, searching systematically. Each item is documented where it lies, with notes, photographs and sketches, before it is moved, because once collected its position cannot be recorded again. It is then collected and packaged in suitable containers, sealed and labelled to preserve the chain of custody.

The other options leave out essential stages: recognition and documentation, or recognition, or everything before collection.

Answer: D

The Frye standard dates from 1923.

In Frye v. United States (1923), the Court of Appeals for the District of Columbia rejected evidence from a systolic blood pressure deception test, holding that a scientific technique must have gained general acceptance in its particular field before expert testimony based on it is admitted. This general acceptance test governed US courts for decades.

1993 is the year of Daubert v. Merrell Dow Pharmaceuticals, which replaced Frye in federal courts with a broader reliability test; 1953 and 1973 are not the years of either standard.

Answer: B

The repetitive pattern is the modus operandi.

Modus operandi (method of operation) is the way an offender habitually commits crimes: the time, the target, the means of entry, the tools and the precautions taken. Because criminals tend to repeat methods that have worked, it helps link crimes and identify suspects.

A signature is a ritual element not needed to commit the crime, reflecting the offender's psychological needs, so it is different from the method. Corpus delicti is the body of facts showing a crime was committed, and 'probability crime' is not a term of criminology.

Answer: D

A secondary crime scene is a site where subsequent criminal activity takes place.

The primary crime scene is where the original offence occurred. Secondary scenes are other places connected with the crime afterwards, such as where a body was dumped, a vehicle used to move it, or where weapons or stolen goods were hidden. Each can yield its own physical evidence.

The place where the crime actually took place is the primary scene. Places of conspiracy or meetings before the crime are relevant to the investigation but are not what the term secondary crime scene describes.

Answer: A

The opening question of a reconstruction is called the investigative question.

Crime scene reconstruction applies the scientific method: the analyst starts from a question the investigation needs answered (who fired first, where the victim was standing, in what order events happened), gathers and examines the physical evidence, frames hypotheses and tests them against that evidence. The question that sets this process going is the investigative question.

A leading question is a courtroom term for a question that suggests its own answer to a witness. 'Associative' describes evidence that links a person to a scene, not a question, and a concluding question would come at the end of the process rather than begin it.

Answer: A

The first school of forensic science was started at the University of Lausanne.

Rodolphe Archibald Reiss founded the Institut de police scientifique there in 1909, the first university programme anywhere devoted to scientific police work. It still trains forensic scientists today.

The University of Saugar (Dr. Hari Singh Gour University, Sagar) was the first Indian university to teach criminology and forensic science, but only from 1959. Michigan and London did not open the first such school.

Answer: A

Both the Assertion and the Reason are true.

A flash fired from the camera position lights the scene flat and straight on, which washes out texture and throws glare back from shiny surfaces. Taking the flash off the camera on a cord lets the photographer light from an angle, so impressions, tool marks and surface detail cast shadows and show up. That is the practice the Assertion describes.

The Reason is also true: even where there is enough available light, a fill flash brightens shadowed corners and brings out detail the camera would otherwise lose. So the options declaring either statement false are wrong.

Answer: C

A suspect's wallet found at the scene is associative evidence.

Associative evidence links a person or object to a place, a victim or another person. A wallet carrying the suspect's documents ties him to the scene directly, which is exactly what this class of evidence does.

Transient evidence is temporary and easily lost, such as odours, temperature or wet footprints. Pattern evidence is a mark or arrangement, such as bloodstain patterns, glass fracture or tyre marks. Conditional evidence is produced by an action or event and describes the state of the scene, such as whether lights were on or doors were locked. A wallet is none of these.