Thinking about motives has got me thinking about Smoke Screens and Red Herrings. If you are unfamiliar with the terms, it basically means misleading your audience by either hiding information, trying to obfuscate the information or offering false or unimportant information to muddle the issue. In writing, these are common, especially in mystery writing. They have to, or it would be a very short book.
In murder mystery party games there are multiple schools of thought. Some people believe that red herrings are hilarious and necessary because they add challenge to a traditionally light mystery. Others believe that they are unnecesarry because they frustrate the players. Honestly, I see both sides. I've played enough Mystery Party Games to know that it can be written very badly and enrage the players because there was no way to "win". It can also be written very well and not land for the audience because there is too much information and it got lost in the crowd. It has been my experience that even when I write a red herring that is VERY outlandish, and I think NO ONE will believe it, people will pick it up and run with it to the finish line. In my experience, people will make up their own red herrings. I don't include them in large mystery party games at all because the large crowd is already a smoke screen. Getting all the information requires the character to be intentional about seeking out and prying information from every other character. Not everyone who plays is going to be an extrovert much less have played enough of these games to focus in on solving the mystery. People will always be slightly uncomfortable with strangers, being dressed up weird, trying to embody a character and taking in tons of information.
Whether you choose to include a red herring into your story or not, never over saturate your story with them. Red herrings really shouldn't be more than 20% of your total clues and I wouldn't personally go over 10%. The percentage is always scaled down with the size of your group. Remember that 90% of the story is already leading to false ends. Only one person is "guilty", the rest just have motive.
It can be tempting to think of writing a mysetery party game as a competition between you and your audience. If you can trick most of them, you win! If that's your goal, remember that you still want your audience to have fun. Including red herrings can certainly help you acheive the goal of fooling your audience but it will also frustrate your players. So when you are thinking of motive, and including red herrings, don't forget to check your motivation. You'll have much more fun watching your audience enjoy themselves than hoping they don't figure it out.
What's the most outlandish red herring you've ever read? (Communism doesn't count, everyone knows its a red herring ;))