, PLEASE USE THIS DOCUMENT AS A GUIDE ONLY
QUESTION 1
1. A woman scratched the face of an unknown man who tried to rape her, but as the
complainant, she cannot give the police a description of her attacker. The South African Police
Service (SAPS) investigator arrests an unknown man whom they suspect of having committed
the crime. Briefly explain in your own words what you understand by the ‘Locard Principle’.
How do you think the principle can be applied to assist in linking the suspect to the crime in
question? Explain your answer.
The Locard Principle, also known as the contact principle, is based on the assumption that when two
objects or people come into contact with each other, a mutual transfer of physical traces or marks
will occur.¹ In the context of a criminal investigation, this means that the perpetrator will leave
something at the scene (or on the victim) and will also take something from the scene away with
them.²
This principle can be applied to assist in linking the suspect to the attempted rape by focusing on the
physical evidence that was transferred during the contact between the woman and her attacker. The
woman scratched the face of her attacker. According to the Locard Principle, during that struggle,
two key transfers of evidence would have occurred:
Evidence left by the suspect: The attacker's skin cells, blood, or other bodily fluids would have
been transferred from his scratched face to underneath the woman's fingernails.³ This
biological material would be a "trace" found on the complainant that the investigator can
collect.
Evidence left on the suspect: The suspect would also have taken away evidence from the victim,
such as the woman's skin or blood under his own fingernails, or traces of her DNA from the
scratch area on his face.
Therefore, the principle is applied by the investigator to collect this transferred evidence. The skin or
DNA found under the woman's fingernails can be compared to a DNA sample taken from the
arrested suspect.⁴ If the DNA profiles match, it provides objective, indirect evidence that the suspect
was the person who had contact with the complainant, thereby individualising him as the attacker,
even without an eyewitness description.⁵
¹ SEP1503, Corporate Investigation I: Only Study Guide for SEP1503 (Pretoria: University of South Africa, 2014), 27.
² Ibid.
³ Ibid., 28.
⁴ Ibid.
⁵ Ibid., 29-30.
QUESTION 1
1. A woman scratched the face of an unknown man who tried to rape her, but as the
complainant, she cannot give the police a description of her attacker. The South African Police
Service (SAPS) investigator arrests an unknown man whom they suspect of having committed
the crime. Briefly explain in your own words what you understand by the ‘Locard Principle’.
How do you think the principle can be applied to assist in linking the suspect to the crime in
question? Explain your answer.
The Locard Principle, also known as the contact principle, is based on the assumption that when two
objects or people come into contact with each other, a mutual transfer of physical traces or marks
will occur.¹ In the context of a criminal investigation, this means that the perpetrator will leave
something at the scene (or on the victim) and will also take something from the scene away with
them.²
This principle can be applied to assist in linking the suspect to the attempted rape by focusing on the
physical evidence that was transferred during the contact between the woman and her attacker. The
woman scratched the face of her attacker. According to the Locard Principle, during that struggle,
two key transfers of evidence would have occurred:
Evidence left by the suspect: The attacker's skin cells, blood, or other bodily fluids would have
been transferred from his scratched face to underneath the woman's fingernails.³ This
biological material would be a "trace" found on the complainant that the investigator can
collect.
Evidence left on the suspect: The suspect would also have taken away evidence from the victim,
such as the woman's skin or blood under his own fingernails, or traces of her DNA from the
scratch area on his face.
Therefore, the principle is applied by the investigator to collect this transferred evidence. The skin or
DNA found under the woman's fingernails can be compared to a DNA sample taken from the
arrested suspect.⁴ If the DNA profiles match, it provides objective, indirect evidence that the suspect
was the person who had contact with the complainant, thereby individualising him as the attacker,
even without an eyewitness description.⁵
¹ SEP1503, Corporate Investigation I: Only Study Guide for SEP1503 (Pretoria: University of South Africa, 2014), 27.
² Ibid.
³ Ibid., 28.
⁴ Ibid.
⁵ Ibid., 29-30.
