Striving for excellence should be a very important part of being a Police Officer/Detective. Talk to the interviewer about the steps that you take to ensure excellence in everything that you do.
"I absolutely strive for excellence in everything that I do. As a Detective, there is a great amount of pressure, both professionally and personally, to always do my best. I take my duty seriously and continually strive to better myself through additional training and accepting feedback from my peers and Captain."