Sunday, December 4, 2016

logical deduction - Double whammy murder case! What happened?


It's Friday the 13th, and you and a group of 7 friends from the "Survivor" club belonging to University LeMao (A, B, C, D, E, F, and G) go camping.


You're all pretty good friends, and talk quite a bit during their hike up the Mountain named Nuffingwrong. As the talk continues, A gets into an argument with E. B, being A's best friend decides to help out A, only to have F step in and make things worse - F decides to help E (They're best friends, after all). For the next 5 minutes, a constant yelling and screaming pierces your ears. Reluctant to get involved, you take G and head off to find a camping spot. The last thing you hear from that area are the words "I'm gonna kill you, I swear it!" from one of the 4 people arguing, followed by C and D stepping in to stop the fight.


After you find a good spot, you and G head back to rendezvous with the group, and tell them about the great spot you guys picked out. The fight seems to be over, everyone seems to be good friends again, and the night seems cheerful.


As the sun sets, the group heads out to the spot you picked to set up camp, and split up the jobs.




  • A and B go to get firewood.





  • C and D are tasked with setting up the tents.




  • E and F are sent to go get some vegetation (berries and/or fruit) for the nights dinner.




You and G end up with the task of sharpening sticks and going to hunt for small critters to cook.


15 minutes pass since everyone has split off to do their jobs. G mentions to you that he needs to go to the washroom, and heads off into the forest. He comes back a couple minutes later, and the two of you continue with your job. For the next half hour, everything seems calm and serene; you and G are having a great time talking while sharpening sticks, discussing how to properly throw them and what the best form for javelin throwing is, when all of a sudden, two bloodcurdling screams resonate from the direction of the campsite.



The two of you try to rush back to the campsite. You follow as G leads, but you both end up getting lost along the way, and don't arrive at the campsite for another 20 minutes. You find that most of the group is already there, waiting for you. Looking around, you notice that E and F's hands are stained with red liquid, C and D are lying face down on the floor, and B is in a pool of blood - a quick look tells you that he is dead. "Where's A", you ask. Nobody knows - everyone instantly rushes back into the forest to look for him, and it doesn't take long before you find him face down in a river - lifeless.


You all head back to camp, and check on C and D. Touching the back of their heads, you notice that your hands are wet and have become stained with red. You gently wake them up, and it seems that they're alright. C and D tell you that they were knocked out by something - You fill them in on what has happened so far, and start the investigation.


Here's what you know about the members of this social group:




  • A and B are your average Joe's - they're not particularly weak or strong. They're prone to arguments, but they're also very hard working people. They also work a lot better individually.




  • A has OCD and can't stand things being messy.





  • C and D are best friends, and are big time geniuses. Like, 140 IQ type genius. They hate conflict, and they're perpetually scared of everything - fortunately for them, their high IQ leads them to preemptively prevent conflict very often - one thing they've done is jack up their bodies by going to the gym a lot.




  • E and F are nerdy environmental studies majors - they pretty much can't lift more than their backpacks, and they're nature lovers like no other.




  • G is a loner - he's prone to violence, and gets upset at the weirdest things. The group pretty much consists of all his friends.





Checking the area, you notice the following things:




  • There's a pile of firewood at the campsite, piled extremely neatly, but missing the top piece of the triangle.




  • The fire hasn't been started yet.




  • There are some crushed berries near B's body





  • There are no major signs of struggle at the campsite (No scuffle marks, etc).




  • The tents have been set up.




  • You manage to find what seems to be the murder weapon regarding B's murder: A single log (firewood size) with red on the bark. It seems to be blood. It seems to fit perfectly on the top of the pile of firewood previously mentioned.





You do some questioning for each member of the group in order to see if you can find out the truth. Here's what you manage to divine from each person:


A: N/A - he's dead, but you notice an EpiPen when you search his clothing - it seems that he's extremely allergic to raspberries.


B: N/A - he's dead, but upon investigation of his body you notice that the blood loss mainly resulted from a heavy blow to the head. There's firewood under his body, suggesting that he was carrying it at the time of death and fell on top of it after getting hit.


C & D: "We don't know what happened - we were knocked out by someone, and after you woke us up, we've been with you the whole time." You point out that C's hands are red. "That's cus we were eating the berries E and F brought back." You mention that only one of them has stained hands - to which they tell you secretly that they're a couple and that C was feeding D. No one in the group knows about this, and they ask you to keep it a secret.


E & F: "We were out collecting berries - we've made several drops off over there" (They point to a pile of berries in a bucket) "And when we got back from our 3rd round, we saw B lying there, dead. We didn't know what to do, so we screamed!"


G: "I've been with you the whole time. I'll show you where I went to piss if you want..."


Q: What happened that night? Who is/are the killer(s)?


Hints to be posted later - if needed.


Hints/For clarity:




Question: Were E and F together the whole time? Answer: Yes.



EDIT MADE: I changed the wording for the section where you run back to camp with G, for clarity!


Because way too many people are falling for this red herring;



G did not kill B - he doesn't know the way back to camp! If he tried he would never have made it there and back, and pissed, all within 5 minutes. Also, he has no motive.



Because Duncan has the right idea:




B was in fact the person to scream "I'm gonna kill you, I swear it" from the argument.



Because people are giving up - don't give up! Here's a hint!



E and F traveled to a single bush area for berries.




Answer



Some preliminary conclusions





  • "A and B [...] work a lot better individually." So they probably separated while collecting firewood.




  • "A has OCD and can't stand things being messy. [...] There's a pile of firewood at the campsite, piled extremely neatly." So the firewood that's already there was probably brought by A.




  • "There's firewood under [B's] body, suggesting that he was carrying it at the time of death and fell on top of it after getting hit." B was only just bringing his firewood to the campsite when he was attacked.




  • "C and D are tasked with setting up the tents" and later "The tents have been set up", so there seems to be no reason for C and D to have left the campsite. Let's assume they were there all the time.





  • "E and F [...] pretty much can't lift more than their backpacks," so it doesn't look like either of them could have hit B with a chunk of wood hard enough to kill him, or knocked out C and D.




  • The campsite bears "no major signs of struggle" (or, we assume, of bodies having been dragged there), so we can assume B was killed there and C and D were knocked out there.




  • A and B are best friends, so we can assume neither of them killed each other.





  • C and D are best friends, so we can assume neither of them knocked out the other.




  • By the logic now stated in the latest edit to the question, G did not kill B.




Main logical argument


We've now eliminated A, E, F, G, and presumably yourself (unless you're an unreliable narrator) as B's killer, leaving only C and D. Since they were together the whole time, they must have conspired together to kill B. For their motive, I quote from Duncan's answer: "B must have been the one to scream 'I'm going to kill you' in the first argument and we know that C and D work to prevent violence. Being smart, they must have figured that one death is better than 2 deaths." More specifically, D must have been the actual killer since (s)he's the one without red hands and the only red you found on the log was blood.


Now we've eliminated B, E, F, and again presumably yourself as the person who knocked out C and D. So this must have been done by A or G. By the same logic as was used to eliminate G as B's killer, he can't have knocked them out. A also has the best motive as he was B's best friend - perhaps he saw them kill B? The other possibility is that they weren't really knocked out at all and were only faking, but let's assume your observations were correct on this one.



Now we've eliminated B, C, D, and again presumably yourself as A's killer. That leaves E, F, and G. E and F are the ones with a motive, given the earlier quarrel. They were together all the time, and their task was picking berries. So it would've been easy for them to corner A near the stream, kill him with raspberries, and then return to the campsite and scream.


Summary



D (accomplice: C) killed B with a log, in order to pre-emptively stop him from killing E and F. A attacked and stunned C and D in a grief-fuelled rage. E and F killed A with raspberries, motivated by their earlier quarrel.





FULL BREAKDOWN AND SOLUTION (Aify's version, in a sort of story mode)


You are not the murderer, so rule yourself out of both cases.



Ruling out G:



G can't be the murderer of B, as he only had one chance in the first 15 minutes of the night.


Reason 1:



  • Because E and F did not scream until 30 minutes later, after their third trip back, G doesn't make the time slot (Assuming equal length trips since they went to the same bush area each time to pick berries (See hints) - 15 mins per trip).


Time line: 15 mins [G leaves to piss], (E F 1st Round to camp) || 30 mins (E F second round to Camp) || 45 mins (E F 3rd round to camp) {Scream is heard}


By the above time line, you can see that if G killed B, E and F would have discovered the body much sooner.


Reason 2: - G got lost with you going back to camp. He would never have been able to make a 2.5 minute trip there and back, AND take a piss. (You know he actually did take a piss because he offers to show you where he went).


Ruling out A, E and F:


E and F lack the strength to enact the murder of B - even if they mustered enough strength to strike down B, it's highly improbable they could knock out C and D at the same time. Since A and B work better individually, it stands to reason that they split up to collect wood. A got back from his first round sometime before B did, proof being the OCD and the neat pile of firewood. A can't have killed B due to them being besties - furthermore, if A killed B, he would have put the piece of wood back on the pile due to his OCD. Assuming equal trip lengths for E and F, each trip they took lasted 15 minutes. Since tent is finished and E/F didn't scream on the second trip back, the time period of B's murder is between the second trip and the third trip.



How B died:


While A was gone, C took the firewood from the top of the pile and snuck up behind B and struck him with one mighty blow, the blood from the blow splashed onto C's hands, which C masked with the raspberry juice - D, being in love with C, helps to cover up and they come up with the plan of C feeding D (to explain C's hands). C and D, being geniuses, used raspberry juice on the back of their heads and pretended that they were knocked out. E and F, returning from their trip, screamed upon sight of a bloody body. B was the one who said "I'm gonna kill you, I swear it!" The motive of C and D lies in the preemptive prevention of that aggression.


C and D are the killers of B



Ruling people out:


G can't be the murderer of A - G doesn't have stained hands, so if G killed A, G must have drowned him, which would result in him being wet somewhere, either from standing in the water, or from holding A's head in the water. Also, 5 minutes is very little time to go and kill someone, piss, and come back. The fact that G offered to show you where he pissed indicates that it was nowhere near A's murder spot, since it would only cast suspicion on himself if it was near. Here, his honesty is his saving grace.


C and D were together at the campsite - the tent was finished, so they can't have left in the first section of time since they need time to put up the tent. C and D were not wet - meaning they did not drown A. A still had his EpiPen on him at the river - unless C and D left the camp to put it back on him, it would be impossible for C and D to make A get an allergic reaction. It's a severe reaction, it would likely have happened on the spot and A would've instantly used his EpiPen at the camp.


Ruling out B:


Main reason: B and A are besties. B would never harm A.


Sub reason: A also had the opportunity to drop off wood at the campsite before leaving to get more; B was only just returning from his first trip before he was killed. That means that B would not have been able to kill A before A dropped off wood (which was anytime before the second return of E/F, but unlikely to be before the first trip of E/F). If B killed A, B would not have had ample time to get wood and go back to camp. B killing A also doesn't make sense because his hands were not stained, and his clothing was not wet - if he killed A, he would either have to get wet drowning A, or force berries down A's throat, resulting in stained hands.



How A died: Any reason to use A drowning as a cause of death can be instantly discounted because nobody had wet clothing. If anyone were to drown A, they wouldve had to get wet. A wasn't particularly weak OR strong, and would have put up a fight - splashing will ensue.


E and F were extremely scared of A and B, and when they saw A, they knew they had to do something before A helped B kill them. Not having enough physical strength to (literally) take down A without getting themselves harmed seriously, they opted for the option of giving A raspberries (Knowing that he is severely allergic).


You can imagine something like "Close your eyes, A, we found something really tasty in the woods. Can you guess what it is?" Proceed to feed A, stealing his EpiPen, the putting him face down in the water


They take the EpiPen from him while his eyes are closed, and when he dies they put him face down in the river and replace the EpiPen to make it look like a drowning. This makes it look like they can't be the murderers, since they're too weak - but remember they're nerds, and they're smart. To pull this off, they took advantage of A's friendship. "E and F's hands are stained with red liquid" - this is the raspberry juice from their berry picking endeavors, and the key clue to connect A's allergy to E and F's berry picking.


E and F are also the only people who had access to A while he was in the woods within the time line.


E and F killed A


Main List of Red Herrings:




  • G's personality





  • Campfire not lit (this was placed to confuse people)




  • Crushed berries (They came from E and F dropping them when they found B, but it's irrelevant unless you use it as a reason to discount E and F from the murder of B; eg: surprise caused them to drop/squash anything they were holding).




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