Factual error: The plot is about a mosquito who stung the murderer. Although Gary Sinise mentions (correctly) that only female mosquitoes sting, the one caught alive on the table is a male mosquito (look at its antennae). All other mosquitoes used in the episode are female.

Visible crew/equipment: At the beginning when the robot is lifting fingerprints from the suitcase, you can see a person walking around in the background-something not likely when there is a bomb threat.

Plot hole: In episode "And Here's To You, Mrs. Azrael": They state that the heart monitor on "Nicole" never showed any movement at all as she was being smothered, because the killer swapped it out and put it on herself. When Mrs. Rollins was smothering her daughter thinking it was Nicole, her heart rate would have raced and her blood pressure would have gone up a little as she strained to hold the bag over her face. The monitor would have picked that up.

Factual error: Season 3, episode 49 (Not What It Looks Like). Breaking glass with sound is possible, but would not work as depicted in the episode. First, in order to break the glass, you have to force the glass to vibrate at its natural frequency - that is, the frequency at which it would vibrate if it were tapped. Each piece of glass has its own natural frequency, depending on a range of factors including size, chemical makeup, shape, hardness, and manufacturing methods. No single frequency would shatter all the glass in the store at the same time. Finally, in order to break the glass the piece has to be closed-ended. You can't shatter a plate of glass with sound (nowhere for the sound waves to resonate). Please see http://www.madsci.org/posts/archives/feb98/887203231.Ph.r.html

Audio problem: When Mac and co. enter the basement of the house in Queens (the one where the third woman was found) the record player lifts off its needle and moves to another spot on the record, cutting off the sound for a second. However, the music starts again slightly before the needle hits the record.