Blood type classification is an example of what kind of evidence?

Blood type classification is an example of what kind of evidence?

• A. Physical
• B. Trace
• C. Biological
• D. Class

Answer: (D)

The idea being tested is how evidence is categorized by its ability to identify individuals versus groups. Blood type is a trait that can place a biological sample into a broad group (those with type A, B, AB, or O), but it cannot single out a specific person. So, it serves as class evidence—it narrows the suspect pool to a group rather than pointing to one individual. In practice, this means a bloodstain with a particular blood type can be used to include or exclude people who don’t share that type, but it can’t uniquely identify the person who left it. It’s not primarily about the physical nature of the object itself, nor about tiny trace amounts, even though the sample is biological. The key takeaway is the level of identification: class evidence ties the sample to a group, not to a unique person.

The idea being tested is how evidence is categorized by its ability to identify individuals versus groups. Blood type is a trait that can place a biological sample into a broad group (those with type A, B, AB, or O), but it cannot single out a specific person. So, it serves as class evidence—it narrows the suspect pool to a group rather than pointing to one individual.

In practice, this means a bloodstain with a particular blood type can be used to include or exclude people who don’t share that type, but it can’t uniquely identify the person who left it. It’s not primarily about the physical nature of the object itself, nor about tiny trace amounts, even though the sample is biological. The key takeaway is the level of identification: class evidence ties the sample to a group, not to a unique person.