Dgrazian says:
As it currently stands, town can catch mafia spoofing investigators by:
1. Having investigators check clues at (approximately) the same time.
2. Requiring investigators to compare clue results. If there's a mismatch then one of them is fake. Note that the mafia have no way of knowing how many clues exist.
Possible options to fix this:
1. Overhaul the clue system. I might be more inclined to this option than others. I'm not a huge fan of the system - it feels rather clunky, and the various investigation-related abilities don't feel to me like they interact elegantly. With that said, the problem described above is not in itself a reason for an overhaul.
2. Allow the mafia to check clue numbers anytime. Note that with the rules as is, this would give them a way to verify serial killers. Some adjustment would need to be made.
3. <INSERT_IDEA_HERE>
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