Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Survey Safety01:28

Survey Safety

188
Surveying near highways, rough terrain, or power lines involves significant risks. Working along highways is particularly dangerous and requires the use of warning signs and flagmen. It is safest to avoid working directly on roads and use offsets whenever possible. When highway work is unavoidable, it must follow all safety guidelines. Surveyors should wear bright clothing, such as orange reflective vests, to ensure visibility to motorists, coworkers, and hunters. In construction zones, wearing...
188
Design Example: Measuring Distance Between Two Points with Obstructions01:10

Design Example: Measuring Distance Between Two Points with Obstructions

142
When measuring distances in areas with physical obstructions, such as a lake in a field, surveyors must employ techniques to calculate accurate lengths without direct line measurements. One effective method is the offset technique, which allows for precise distance estimation over inaccessible stretches.In this scenario, a surveyor must measure a side of an area that crosses a lake. Since the measuring tape cannot span the lake, the surveyor begins by establishing a baseline that aligns with...
142
Profile Leveling and Cross Sections01:26

Profile Leveling and Cross Sections

689
Profile leveling and cross-sections are surveying methods used to determine and document terrain elevations for infrastructure projects such as highways, railroads, canals, and pipelines. These methods provide data for earthwork planning and alignment of proposed routes.  Profile leveling involves measuring elevations along a fixed line to create a vertical terrain profile. A surveyor sets up a leveling instrument at the benchmark (BM) and records a backsight (BS) to determine the...
689
Introduction to Surveying, Plane Surveying and Geodetic Surveys01:27

Introduction to Surveying, Plane Surveying and Geodetic Surveys

473
Surveying is the art and science of mapping the earth's surface. It involves measuring distances, angles in horizontal or vertical directions, and levels to understand the shape and size of land features. Surveying techniques are essential for various tasks, such as identifying the levels of a land area with reference to a specific point, and mapping undulations and water bodies.There are two main types of surveying: plane surveys and geodetic surveys. Plane surveys assume the earth is flat,...
473
Common Leveling Mistakes and Errors01:17

Common Leveling Mistakes and Errors

139
A survey team is tasked with determining the elevation difference between points Point A and Point B, separated by uneven terrain. They use a leveling instrument and a leveling rod.Common MistakesMisreading the Rod: During a backsight reading at Point A, the instrumentman observes the rod partially obscured by tall grass. Instead of reading 1.135 m, they mistakenly record 1.735 m due to the misalignment of the crosshair with the wrong graduation. This error adds 0.600 m to all subsequent...
139
Errors and Mistakes in Surveying01:19

Errors and Mistakes in Surveying

262
Errors and mistakes in surveying refer to inaccuracies in measurements and data recording. The errors are deviations from the actual value caused by human sensory limitations, equipment flaws, or environmental effects. These errors are typically unintentional and can result from the inherent imperfections in the instruments used, atmospheric conditions, or the observer’s inability to perceive exact measurements. On the other hand, mistakes are caused by the surveyor's lack of...
262

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Assessing the foundations of forensic identification evidence: A critical examination of proficiency test design and results.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

A Framework for Estimating the Value of Deterrence.

International Topical Meeting on Probabilistic Safety Assessment and Analysis (PSA 2019) Charleston, SC, April 28-May 3, 2019. International Topical Meeting on Probabilistic Safety Assessment and Analysis (2019 : Charleston, S.C.)·2025
Same author

Author response to Commentary on "Accuracy and reproducibility of bullet comparison decisions by forensic examiners".

Forensic science international·2025
Same author

Ineffectiveness of the "consistent with" judicial limitation on forensic firearm identification testimony.

Law and human behavior·2025
Same author

Partitioning the Expected Value of Countermeasures with an Application to Terrorism.

Decision analysis : a journal of the Institute for Operations Research and the Management Sciences·2025
Same author

The Hawthorne effect in studies of firearm and toolmark examiners.

Journal of forensic sciences·2025

Related Experiment Video

Updated: Sep 24, 2025

A Cross-Disciplinary and Multi-Modal Experimental Design for Studying Near-Real-Time Authentic Examination Experiences
08:33

A Cross-Disciplinary and Multi-Modal Experimental Design for Studying Near-Real-Time Authentic Examination Experiences

Published on: September 4, 2019

7.1K

Surveying practicing firearm examiners.

Nicholas Scurich1, Brandon L Garrett2, Robert M Thompson3

  • 1University of California, Irvine, USA.

Forensic Science International. Synergy
|May 5, 2022
PubMed
Summary
This summary is machine-generated.

Firearm and toolmark examiners spend hours on casework. While most identify firearms, few cite studies for error rates, and views on statistics in testimony are mixed.

Keywords:
Error ratesExpert testimonyFirearms and toolmarks examinationForensic conclusionsForensic science

More Related Videos

Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue
07:09

Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue

Published on: May 9, 2019

8.2K
A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
09:12

A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation

Published on: June 28, 2015

8.7K

Related Experiment Videos

Last Updated: Sep 24, 2025

A Cross-Disciplinary and Multi-Modal Experimental Design for Studying Near-Real-Time Authentic Examination Experiences
08:33

A Cross-Disciplinary and Multi-Modal Experimental Design for Studying Near-Real-Time Authentic Examination Experiences

Published on: September 4, 2019

7.1K
Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue
07:09

Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue

Published on: May 9, 2019

8.2K
A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
09:12

A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation

Published on: June 28, 2015

8.7K

Area of Science:

  • Forensic Science
  • Firearm and Toolmark Examination

Background:

  • Firearm and toolmark examination is a critical forensic discipline.
  • Understanding current casework practices and examiner perspectives is essential for advancing the field.

Purpose of the Study:

  • To survey practicing firearm and toolmark examiners on their casework practices.
  • To gather insights into examiners' views on the role of statistics in firearm examinations and expert testimony.

Main Methods:

  • A survey was distributed to 79 practicing firearm and toolmark examiners.
  • Data collected included time spent on examinations, identification/elimination/inconclusive rates, and opinions on statistical applications.

Main Results:

  • Modal time for bullet examination: 2-4 hours; for cartridge casings: 1-2 hours.
  • Median examiner identification rate: 65%; elimination rate: 12%; inconclusive: 20%.
  • Reported false positive rate: 1%, with limited citation support; mixed views on statistics.

Conclusions:

  • Current casework practices show significant time investment and specific outcome distributions.
  • A notable gap exists in the empirical support for reported error rates.
  • Examiner opinions on integrating statistics into firearm examination and testimony are varied.