Continuity mistake: Season 2, Episode 17: "Could I Leave You?" - When Mr. Beale throws a pencil into his mug, the pencil can be seen on his desk in the shot immediately afterwards.
Look Into Their Eyes and You See What They Know - S5-E19
Other mistake: In an earlier episode where Edie and Susan are driving Martha Huber's ashes to the lake to be spread, Edie gets a flat tire and Susan changes it. In this episode, all the girls are driving with Edie's ashes and they get a flat tire. Susan asks "Does anyone know how to change a flat tire?" Did she forget how?
Gabrielle: I feel a wave of morning sickness coming on, and I want to be standing on your mother's grave when it hits.
Trivia: Teri Hatcher (Susan), Felicity Huffman (Lynette) and Eva Longoria (Gabrielle) are the only cast members to appear in every single episode of the series.
More questions & answers from Desperate Housewives
Answer: He was investigating the lead not the case.