JESS: I’m not really familiar with the blue book laws in this town, so you can be talking about a lot of things. Dropping a gum wrapper, strolling arm in arm with a member of the opposite sex on a Sunday.
Jess seems to have confused two different things and put them together (perhaps deliberately).
Blue laws are laws designed to restrict activities on a Sunday, such as banning certain retail activities eg buying alcohol. In Puritan times, they were very strict when Connecticut was a colony, which might be what Jess is implying – that Stars Hollow is still stuck in the colonial past. Examples of such old timey strictness include not allowing people to run anywhere, or to walk in their gardens on a Sunday. It’s not common, but some towns in the US do have their own blue laws, even today.
Project Blue Book was the code name for the study of UFOs by the US Air Force from 1952 to 1969. Did Jess make a simple error, a Freudian slip of the tongue, or is he saying that he feels like an “alien” being studied by the townsfolk of Stars Hollow?
(I have actually seen people make this same error in regard to “blue book laws”, so I don’t discount the idea that the writer, Daniel Palladino, may have had the same misunderstanding).