Answer:
As I was interviewing the victim's family to get enough information for my counterpoint of the police's theory, their excessively emotional state accounted for frequent drawbacks.
Step-by-step explanation:
The noun "drawback" refers to a disadvantage or a problem, the negative part of a situation. The noun counterpoint is frequently used to refer to a technique in music, but it can also refer to the action of contrasting two things - arguments, themes, ideas etc.
In the answer provided above, the speaker is interviewing the family of someone who has been a victim of a crime. The interviewer's intention is to obtain information that can counterpoint - that can compare and contrast - the police's theory on what happened. The drawback - the disadvantage, the problem - is that the family is still too emotional, which makes the interview more difficult and less reliable.