**9. Conclusions**

A significant aspect of many forensic investigations is the interpretation of tool marks that may have an impact on a number of disciplines, including anthropology, archaeology and pathology. The reason for the determination of the tool mark is not specific but usually refers to the recognition, adjustment and comparison

**99**

*Forensic Analysis and Interpretation of Tool Marks DOI: http://dx.doi.org/10.5772/intechopen.98251*

made it.

to organizational activities.

long history.

**Conflict of interest**

**Acronyms and abbreviations**

"The authors declare no conflict of interest."

TRAX Tool Mark Imaging System Database

AFTE Association of Weapon and Tool Mark Examiners

of the marks/indentations left on the surface after contact with the tool. Mark evidence involves the analysis of any object where a mark or impression has been rendered during criminal conduct to link the mark with the object or tool that

The AFTE argues that the idea of identification appears contextual, an evaluation that helps researchers to establish protocols that are more precise and detailed. However, new technologies and tools provide the forensic community with a new basis and support to understand, refine and spread the methodology to the experts, which helps to interpret the marks of the tool. Technologies used in surface characterization is constantly changing, and computers are becoming more and more efficient, making it less burdensome for extensive computations, so new methodologies can be more sophisticated. These modern methodologies generally involve first converting a tool mark scan to a digitized striae depth representation in given distances along the mark, collected using a profilometer or similar tool, rather than manually aligning two photographs or imprints of the tool marks. Forensic databases can provide a measure of the accuracy of the identification of certain recognition characteristics, helping to become beneficial in the analysis of evidence. The results of the use of databases will apply not only to court documents but also

When evidence marks are forwarded for analysis, the investigator shall be given four plausible explanations when assessing the marks: recognition, inconclusive, elimination or unacceptable. Examiners often come down on the side of uncertainty and only accept identification when this conclusion is unanimously accepted. The anticipated qualities of a forensic evaluation are defined by four principles: rational, unambiguous, balanced and rigorous, facilitating the field to transition from a collection of concealed secrets within professionals to a formal body of information from which one can be qualified to be an examiner. Therefore, it is evident that tool mark evaluation and interpretation are complex operations requiring consideration of several intrinsic and extrinsic variables, and so it is not surprising that this is a field of research that has attracted significant interest and discussion over a fairly

#### *Forensic Analysis and Interpretation of Tool Marks DOI: http://dx.doi.org/10.5772/intechopen.98251*

*Forensic Analysis - Scientific and Medical Techniques and Evidence under the Microscope*

that can be used in court should be generated [25, 26]:

material from known potential sources).

specified by the mandating authority.

first stated in an AFSP paper [27]:

proof cannot be measured.

he came to his inference.

the report.

Additionally, after these two requirements are accomplished, evaluative reports

• A mandating authority or party has asked the forensic practitioner to analyze and/or compare material (typically recovered trace material with reference

• The forensic practitioner attempts to evaluate findings in relation to specific conflicting propositions established by the unique case circumstances or as

In court, the results of forensic examinations should be evaluated using a probability ratio relying on the findings, associated data and expert knowledge, casespecific propositions and conditioning information. Since the value of the results is dependent on the case information and propositions, this should be emphasized in

The forensic expert opinion should be carried out on the basis of four precepts

• Balance: in order to reinforce the truth, the expert should accept at least one pair of the hypothesis proposed by the prosecution and defense, and if it is not possible to find a reasonable alternative for any reason, the expert will be able to examine only one proposition, but will make it clear that the strength of the

• Logic: evaluative reports should address the likelihood of the findings given the propositions and relevant background information, rather than the likelihood of the propositions given the findings and background information. Statements

• Robustness: the opinion of an expert should be resilient and satisfy the reliabil-

• Transparency: by addressing and evaluating hypotheses, examination results, and theoretical facts, it would be necessary for the expert to demonstrate how

To be these above things, experts need to make it express exactly what they have done and with what technique, what highlights have been thought of and why, what grants have been made and why and, last and most importantly, by unmistakably spreading out an indictment and a defense viewpoint upon which to consider the outcomes. These perspectives will without a doubt be restricting and, in instrument mark assessments, as a rule address the expected wellspring of the mark(s). The indictment view that "the submitted tool made the scene mark" is not hard to

A significant aspect of many forensic investigations is the interpretation of tool marks that may have an impact on a number of disciplines, including anthropology, archaeology and pathology. The reason for the determination of the tool mark is not specific but usually refers to the recognition, adjustment and comparison

that transpose the conditional should not be included in the report.

ity standards set by other experts for cross-examination.

**98**

define [28].

**9. Conclusions**

of the marks/indentations left on the surface after contact with the tool. Mark evidence involves the analysis of any object where a mark or impression has been rendered during criminal conduct to link the mark with the object or tool that made it.

The AFTE argues that the idea of identification appears contextual, an evaluation that helps researchers to establish protocols that are more precise and detailed. However, new technologies and tools provide the forensic community with a new basis and support to understand, refine and spread the methodology to the experts, which helps to interpret the marks of the tool. Technologies used in surface characterization is constantly changing, and computers are becoming more and more efficient, making it less burdensome for extensive computations, so new methodologies can be more sophisticated. These modern methodologies generally involve first converting a tool mark scan to a digitized striae depth representation in given distances along the mark, collected using a profilometer or similar tool, rather than manually aligning two photographs or imprints of the tool marks. Forensic databases can provide a measure of the accuracy of the identification of certain recognition characteristics, helping to become beneficial in the analysis of evidence. The results of the use of databases will apply not only to court documents but also to organizational activities.

When evidence marks are forwarded for analysis, the investigator shall be given four plausible explanations when assessing the marks: recognition, inconclusive, elimination or unacceptable. Examiners often come down on the side of uncertainty and only accept identification when this conclusion is unanimously accepted. The anticipated qualities of a forensic evaluation are defined by four principles: rational, unambiguous, balanced and rigorous, facilitating the field to transition from a collection of concealed secrets within professionals to a formal body of information from which one can be qualified to be an examiner. Therefore, it is evident that tool mark evaluation and interpretation are complex operations requiring consideration of several intrinsic and extrinsic variables, and so it is not surprising that this is a field of research that has attracted significant interest and discussion over a fairly long history.
