Corrected entry: Martin says in the pilot "two years ago I'm sailing toward retirement and some punk robbing a convenience store puts a bullet in my hip." In another episode he says to Niles "sometimes when life closes a door, you need to kick one open...of course last time I did that on a raid, the guy on the other side shot me in the hip."
Corrected entry: Early in the run of Frasier, Lilith arrives in Seattle for a visit. Niles is very cold with her, because he says "at our wedding when Maris was reciting her vows, which she wrote herself, vows of love from the heart, I distinctly heard snickering." Niles had been married to Maris for 15 years when they separated during the 3rd or 4th season. How then could Lilith have been at their wedding? At that time Frasier would have not have even known Lilith, and was probably involved with Diane Chambers.