Question 1

The results of an experiment are admissible at trial only if the person who conducted the experiment testifies.

Accepted Answer

The results of an experiment can be admissible as evidence if a qualified expert witness who did not conduct the experiment testifies about the results and their significance.

Question 2

The "chain of custody" must be established before the prosecution can admit crime scene evidence at trial.

Accepted Answer

The "chain of custody" refers to the documentation of the history of the evidence, including how it was collected, handled, and stored. This documentation is necessary to ensure that the evidence has not been tampered with or contaminated since it was collected. Before crime scene evidence can be admitted at trial, the prosecution must establish the chain of custody to show that the evidence is authentic and reliable.

Question 3

Evidence that has been discolored or otherwise changed by laboratory tests is not admissible at trial.

Accepted Answer

Evidence that has been discolored or otherwise changed by laboratory tests may still be admissible at trial, but its reliability and accuracy will be subject to scrutiny and challenge by opposing counsel.

Question 4

Items that the police recover from the crime scene must be sealed in air-tight, tamper proof containers.

Accepted Answer

While it's crucial for police to properly secure and preserve evidence from a crime scene, not all items need to be sealed in air-tight, tamper-proof containers. The method of packaging can vary depending on the nature of the evidence (e.g., biological samples, firearms, documents).

Question 5

To use latent prints at trial, the prosecutor needs to call the person who recovered the prints and the person who identified them.

Accepted Answer

In order to use latent prints at trial, the prosecutor needs to call the person who recovered the prints and the person who identified them as expert witnesses.

Question 6

Familial DNA testing is used to establish paternity but is not admissible in criminal court.

Accepted Answer

Familial DNA testing is not only used to establish relationships such as paternity but is also admissible in criminal courts to help identify suspects through their family members' DNA.

Question 7

To be admissible, an experiment must be conducted under the same conditions as those that existed at the time of the crime (or event in question).

Accepted Answer

This is known as the principle of a forensic experiment, which means that the conditions of the experiment should match the conditions of the crime or event being investigated for the results of the experiment to be admissible in court.

Question 8

Examination of a recovered bullet produces useful information only if the gun from which it was fired has been recovered.

Accepted Answer

Ballistic experts can gather valuable information from a recovered bullet, such as the type of firearm used, caliber, and sometimes the manufacturer, even if the gun itself has not been recovered. This information can help in the investigation by narrowing down the search for the weapon or linking the bullet to other crimes.

Question 9

An attorney must lay the proper foundation prior to introducing any type of real evidence.

Accepted Answer

This is true. The attorney must establish the authenticity and relevance of the evidence before it can be admitted in court. This is done by laying the proper foundation, which means providing a sufficient basis for the judge to understand why the evidence is being offered and how it is related to the case. Failure to lay the proper foundation can result in the evidence being excluded.

Question 10

Any scientific test can be challenged based on faulty test equipment.

Accepted Answer

Faulty test equipment can lead to inaccurate results, which can undermine the validity of any scientific test. Therefore, tests can be challenged based on faulty test equipment.

Question 11

A ballistics expert is used exclusively to determine if a bullet was fired from a particular gun.

Accepted Answer

A ballistics expert not only determines if a bullet was fired from a particular gun but also analyzes bullet trajectories, gunshot residues, and other firearms-related evidence to reconstruct shooting incidents.

Question 12

In a case involving driving under the influence of alcohol, a blood test must be used to establish the blood alcohol level of the suspect.

Accepted Answer

Other methods, such as breathalyzer tests, can also be used to establish the blood alcohol level of a suspect in cases involving driving under the influence of alcohol.

Question 13

The only thing a defense attorney can do to refute the results of scientific tests performed in government labs is to have the sample tested in an independent lab.

Accepted Answer

A defense attorney can also challenge the validity of the scientific tests by questioning the methods used, the qualifications of the personnel, the condition and maintenance of the equipment, and the chain of custody of the sample, among other strategies, without necessarily having the sample tested in an independent lab.

Question 14

Crime scene evidence is authenticated by the use of laboratory tests.

Accepted Answer

The answer of Crime scene evidence is authenticated by the...

Question 15

All items of real evidence are marked and reviewed by the judge prior to the start of the trial.

Accepted Answer

Real evidence may be presented and marked during the trial, and it is up to the judge to determine its admissibility based on relevance and other legal criteria at the time it is offered.

Question 16

Analysis of drugs (controlled substances) accounts for the majority of scientific tests done in government crime labs.

Accepted Answer

The answer of Analysis of drugs (controlled substances) accounts for...

Question 17

In cases involving seizures of large quantities of controlled substances, all the drugs seized must be tested to establish their identity.

Accepted Answer

Typically, a representative sample of the seized substances is tested to establish their identity, not the entire quantity, due to practicality and resource constraints.

Question 18

A search warrant is required to obtain any real evidence from the defendant for testing.

Accepted Answer

While a search warrant is often required to obtain real evidence from a defendant, there are exceptions where evidence can be obtained without a warrant, such as with consent, during a lawful arrest, in situations with exigent circumstances, or under the plain view doctrine.

Question 19

Luminol is used to field test suspected drugs to determine if they contain cocaine.

Accepted Answer

Luminol is not used to test for drugs or drug substances. It is a chemical reagent used to detect the presence of blood at crime scenes.

Question 20

Identification based on blood typing is more accurate than DNA testing.

Accepted Answer

DNA testing is considered more accurate for identification because it provides a unique genetic profile for each individual, while blood typing can only determine the type of blood present.

Quiz 7: Crime Scene Evidence and Experiments