Question

DNA evidence analysis is an imperfect science. Provide two reasons why this may be the case.

Answer 1

Answer:

Not all DNA that was found at the scene has to be related to the scene.

Explanation:

Just because DNA was found at the scene, that doesn't mean that the person there is actually guilty. For example, in a case where person B is guilty, a strand of hair from Person A could be carried over to another scene on Persons B's clothing.