During the intro scene, when Jerry announces his retirement day holding a box, a tiny Indiana state flag keeps appearing and disappearing from it.
The gravestone for Mayor Knudson has the dates 1936-1985 inscribed. However, the "Pawnee Journal" that Leslie holds up featuring an article on Knudson's death is dated Friday, March 11, 1984. Additionally, March 11, 1984, was a Sunday, not Monday; March 11, 1985, was a Monday.
The security guard says guests are only allowed in the city council dining room on Wednesdays. There's only 7 people on the city council yet the dining room is filled with dozens of people.