Chapter 17. Squirrel Falls

 

Monday morning Alan Quick sets up a private meeting with Judge Laura Mae Hopper. He gives her the written summary of Mary Anderson’s findings. After she’s read it he tells her he’s carefully reviewed the evidence and is convinced Squirrel is the robber of the check-cashing stores in Detroit and the killer of two people in his last robbery. He is also convinced Squirrel killed Martha Crawford. He says, “I think we have probable cause to hold him for the robberies and murders in Detroit. That will prevent him from running again while we look for more evidence tying him to Martha Crawford’s murder.”

Judge Hopper replies, “With all the probabilities there must be a probable cause pun, I just can’t think of it.” After their laughing stops she continues, “I agree, you have probable cause to issue a warrant for his arrest for the suspicion of the robberies and murders in Detroit. In fact, you might get away with arresting him without probable cause. With his background, the sheriff could say he’s enough of a flight risk to arrest him. What do you want me to do?”

Quick says, “I want a warrant to search Squirrel’s home, motorcycle, and anywhere he might have something that connects him to the Crawford case. I believe Squirrel having an injury likely leaving him with a scar on his forehead, Martha witnessing a killer with a scar on his forehead, and Squirrel being at the gift shop the day she was murdered is enough to justify a search warrant.”

“I agree. I’ll give you a search warrant. How are you going to make sure Sheriff Ericsson doesn’t do something stupid and cause Squirrel to vanish?”

The prosecutor replies, “I’ll tell the sheriff if he wants my support in the future he’ll have to follow my directions to arrest and jail Squirrel. Deputy Wilson is skilled at approaching suspects in ways not alerting them they are under suspicion. I intend to sit down with the sheriff and Wilson. We’ll devise a plan to arrest Squirrel before he can vanish again.”

“Okay, Alan. Submit your search warrant. I’ll sign it and hold it until you tell me Squirrel is behind bars. We can wait on an arraignment long enough for the sheriff to conduct the search. If he finds anything connecting Squirrel to the Crawford case we can arraign him for Martha’s murder. If no evidence is found we’ll arraign him for the Detroit robberies and murders. I know everyone in Pineville would like to see him convicted of the Crawford murder instead of giving him to Detroit. Make sure Sheriff Ericsson takes a new mugshot of Squirrel and sends it to each of the police departments in metropolitan Detroit reporting a check-cashing store robbery. I hope showing his picture to the store owners will provide proof of what the AI software tells us is highly probable. Those police departments can close the open robbery cases connected to Squirrel if he’s identified and we have him in custody. Most important, as soon as Squirrel is in custody, I’d like you to contact the woman whose husband and daughter were murdered. Tell her we believe we have her husband and daughter’s murderer in jail. Maybe it’ll give her a little peace.”

Quick thanks the judge and adds, “If we close the Crawford case, and the Detroit area police close all of their cases involving the Squirrel, it suggests this new artificial-intelligence-based approach has the potential to revolutionize criminal justice.”

Judge Hopper says, “Yes, I think it does. Let’s hope we can connect Squirrel to his crimes with traditional identifications and physical evidence. Convicting someone based solely on probabilistic predictions by unproven software would certainly result in appeals. Let’s avoid that path if we can.”

 

Back in his office, the prosecutor calls the sheriff’s office. He asks Sue Johnson to set up a meeting with the sheriff and Deputy Wilson and call back when she has a meeting time. Five minutes later Sue calls and says Wilson will be back from patrol at 11:00 and they can meet then. He tells her he’ll be at the sheriff’s office at 11:00.

 

When Quick arrives for the meeting he tells Wilson to give him five minutes privately with the sheriff. Quick then goes into the sheriff’s office and closes the door. He says to the sheriff, “I have good news on the Crawford case. It’s going to make us heroes in Pineville if you are patient and do your job the way I’m going to tell you. If you want my support in the future you’ll follow my direction. Do you understand?” Quick looks the sheriff directly in the eyes and waits for his reply.

The sheriff looks bewildered. After a brief pause, he replies, “If it’ll make us heroes I’ll follow your direction.”

Quick opens the office door and invites Wilson in. He tells them what he has learned from Mary Anderson's work. They are astonished. The sheriff asks how Quick knows this fancy software works. Quick says he doesn’t know. He tells the sheriff they don’t need to understand it. Sheriff Ericsson tells the prosecutor he wondered if the killer faked the rape to make everyone on the sex offender registry suspects instead of the real killer. He says Squirrel’s attempt to divert suspicion away would have worked without the new approach to investigations.

Quick gives the sheriff an arrest warrant for Squirrel and says, “We need to get this guy behind bars before we learn he’s left Pineville. I want it done in a foolproof way. I want to hear how Wilson will do it if we send him for Squirrel. Wilson, do you have an approach that won’t spook Squirrel until you have him in cuffs?”

Wilson thinks for a moment then looks at the sheriff for guidance. The sheriff nods indicating Wilson can share his approach. Wilson says, “I’ll take a picture with my cell phone of the biggest tree I can find close to a building. I’ll take the picture to Tommy’s Tree Trimming and ask Tommy if the tree can be removed without damaging the building. Whether Tommy says yes or no, I’ll say I want to hear it from the guy who’s going to climb the tree. If Tommy doesn’t bring Squirrel in I’ll say Billy Red Deer told me Squirrel is the best climber. I want to hear it from Squirrel. The moment Squirrel looks at the picture I’ll arrest him. I’ll take Deputy Towner with me. Towner can act like he’s not interested in tree climbing so he doesn’t spook Squirrel. He’ll be my backup if Squirrel resists.”

Quick says, “That sounds good to me. What do you think, Sheriff? Will Wilson’s plan work?”

The sheriff says, “It’s a good plan. I’m confident Wilson can pull it off. I’ve seen how casual he can be. He’s convincing.”

The prosecutor says, “Okay, put the plan in motion. The moment Squirrel is behind bars Judge Hopper will give you a search warrant for Squirrel’s home, motorcycle, and anywhere he might have something connecting him to Martha Crawford. While the search is underway I’ll get you a list of police departments in the Detroit area where we’re convinced Squirrel committed robberies. Judge Hopper wants you to send each one a new mugshot of Squirrel. They may be able to close some old robbery cases.”

The sheriff asks, “Was Pamela Lafave involved in getting this new evidence?”

Quick says, “Yes, she played a role along with the others on the board of Doc Arra’s museum.”

Sheriff Ericsson turns red and says, “I hope Mary Jane Bloom doesn’t find out. She’ll have a field day making sure everyone knows I had to have Pam Lafave’s help solving this crime.”

“Sheriff, you get Squirrel behind bars, execute a good search and you’ll get the credit. I’ll talk to the mayor. I think he may be able to have Mary Jane Bloom see this as a victory for Pineville, not a humiliation for you.”

“Thank you, Alan.” Turning to Wilson the sheriff says, “Wilson, get Towner and go arrest Squirrel. Do it by the book. We don’t want some lawyer to get this case thrown out.”

Wilson leaves, followed by the prosecutor.

 

At 4:30 Quick gets a call from an excited Sheriff Ericsson. The Sheriff says, “We did it. Squirrel’s behind bars. Sue Johnson has sent his new mugshot to each of the police departments on the list you sent me. The search paid off. Wilson found Martha Crawford’s missing signet ring in a saddlebag on Squirrel’s motorcycle. Now we only have to go through all the legal steps to put Squirrel away for life. The Crawford case is as good as closed. Want to join the deputies and me at the Corner Bar to celebrate? We are going there right after I call the Crawfords and tell them we have Martha’s killer in jail. I want them to know we’re convinced Martha was strangled but not raped before she died.”

“Good job, Sheriff. That’s news all Pineville will celebrate. I’ll pass on your invitation. I intend to celebrate with a certain lady tonight. She’ll be pleased the Crawford case is as good as closed too. You go celebrate. I’ll call the mayor. He may want to join you at the Corner Bar after he calls Mary Jane Bloom.”

 

 

 

 

 

 

 

 

 

Acknowledgments

My thanks to retired policewoman Katie Lajoie for advising me on allowed and not quite allowed police interrogation techniques, and to Judge Laura Frawley for advising me on proper processes for warrants. If I have bent the rules it’s only due to my misinterpretation of their advice.

Chapter 16. Pam Takes Charge

 

Alan Quick calls Pam during his lunchtime on Friday asking her to go to the Italian restaurant for dinner that night. Pam says, “I’d love to have dinner with you, Alan. Instead of going out would you mind coming to my farm for dinner? I want to talk to you privately.”

Alan replies, “Tell me what time and I’ll be there. Shall I bring a bottle of Chardonnay?”

“Chardonnay will be great. I’m planning on having whitefish fillets and fresh vegetables from my garden. Come at 6:30 if you can make it that early.”

“I’ll see you at 6:30,” says Alan.

 

They are having coffee with Pam’s fresh-baked cherry pie for dessert. Alan asks, “You said you have something private to talk about. What’s on your mind?”

“Martha Crawford was a friend. She volunteered at many places in Pineville, including at Doc Arra’s museum where I’m a board member. Neither I nor most of the other board members believed the story being spread around town by gossip and Mary Jane Bloom’s column that the rapist left the area. We believe the sheriff concocted the story to quiet the fears running rampant due to Mary Jane Bloom’s earlier inflammatory columns. I understand why he may have done it; women were afraid to go out of their homes. I don’t know how he got Mary Jane to support his story, but it doesn't matter.”

“Oh, I think I know why she supported the story the sheriff and his deputies were spreading. The mayor’s secretary, Marylynn overheard the mayor talking to the sheriff. She plays bridge with my secretary, Marge. Marylynn told Marge she heard the mayor say he would make sure Mary Jane Bloom’s column would support whatever they were up to. Marge told me Marylynn didn’t hear enough to know what they were planning. Knowing how Mary Jane likes to ridicule our sheriff she must have been pressured to support the stories he was spreading. It makes sense to me the mayor and the sheriff planned how to calm fears in Pineville when the sheriff failed to catch Martha Crawford’s killer. Honestly, I can’t blame them.”

“And it worked for many people. Some, like Peter Brown, who’s on our museum board believed because he wanted his wife’s fear stopped. Anyway, the museum board members, including me, decided to continue to look for Martha’s killer. Sam Weiss, another board member, has a nephew who is a professor at the University of Michigan’s Dearborn campus. The nephew; his name is Jim, is part of a team developing a new approach for police investigations. It uses the techniques social media companies developed for targeted ads. It combines those techniques with human sciences and existing criminal databases. Maybe other data I don’t recall. Artificial intelligence is used to analyze all of the data. If you want more detail on the software algorithms Sam Weiss can explain it for you.”

“I doubt I could understand any more detail. What you say makes sense to me. I am always amazed to see how ads pop up in my email when I am thinking about buying something. If the ad companies can tell what I am planning to buy then I guess it’s possible to learn stuff about criminals. So, do you have access to this new software?”

“Yes, Sam arranged it and arranged for Jim to explain to Mary Anderson how to use it. It has to be run on private networks if data on people without a criminal record is added due to privacy issues. We added Martha Crawford’s personal data with her parent's permission. Mary is accessing the new software from the State network she uses at the Courthouse. She’s doing it on her own time so she’s not doing anything wrong I know of.”

“Interesting. Has she learned anything new about the Crawford case?” asks Alan.

“Yes, we are convinced we know who killed Martha and why. The person is living and working locally. In short, we have a motive, means, and opportunity. But we don’t have any physical evidence connecting the killer to Martha. I am concerned if we take what we have to Sheriff Ericsson; he’ll jump the gun and either get the case dismissed again or scare the killer into running. The reason I wanted to talk to you about it is I hope you are willing to help us put Martha’s killer behind bars.”

“Absolutely, I want to see Martha’s killer caught as much as anyone. And it’ll be good for my career to successfully prosecute her killer. What do you want me to do, Pam?”

“First, I want you to review the evidence we have. The best way is to have Mary Anderson show you step by step what she has. Then, if you are as convinced as we are that the analysis points to Martha’s killer we want you to tell us the best way to proceed so we do things legally and not scare the killer into running.”

“That makes sense. If you convince me I think the best approach is for me to take your evidence to Judge Hopper, tell her my approach for apprehending the suspect and see if she’ll sign the warrants I expect will be needed. You may have enough to arrest the suspect on suspicion of murder and keep him in jail long enough to put a solid case together. I shouldn’t speculate any further until I see the evidence. When can you arrange for Mary Anderson to show me the evidence?”

“If you are free tomorrow afternoon I’m sure Mary will meet then. We can do it right here. Come for lunch if a big salad interests you. My garden is overflowing and I hate to see it go to waste.”

“A salad of fresh greens from your garden sounds wonderful. Shall I bring something?”

“No, I have everything I need. Now, want to help me do the dishes before we go sit on the porch and watch the sunset through the cedars? There’s still a half bottle of the chardonnay left.”

“Sure, here I thought I was earning my dinner just by listening to your story.”

“Nice try, Alan. I’ll wash, you dry.”

 

Saturday morning Pam calls Mary, tells her Alan Quick is willing to help and invites her for lunch. She says Alan wants to see all her evidence on the Crawford case. Mary is happy to come with the evidence.

After their salads, Mary walks Alan through the process she used and the resulting probabilities. She says, “I did a couple more runs this morning. I wanted to see if the AI algorithm could tell us the probability Squirrel would rape a woman or fake rape to throw suspicion on others. The results strongly indicate he would not commit rape but he would fake rape to divert suspicion from himself. It’s going to be a little comfort for Martha’s parents to know she wasn’t raped before she was strangled.”

When she finishes Alan looks puzzled for a few moments. He says, “I’m not used to thinking about probabilities. I hated the statistics we had to study in freshman math. I hoped I’d never have to see that stuff again. I do remember enough to know that probabilities less than 10% don’t mean a connection and probabilities as large as you are showing me do mean a connection.”

Mary says, “You’ve remembered it almost correctly, Alan. The probabilities we have are significant and strongly suggest a connection, but they don’t prove a connection. For proof, we would want to see three-sigma results but never mind that. In Pam’s language, we have good evidence of motive, means, and opportunity. We know that’s not quite enough to convict Squirrel. That’s why Pam asked for your help.”

“But doesn’t the fact these high probability pieces of evidence naturally fit together increase the overall probability?” asks Alan with his puzzled look again.

“I think so, Alan, but I don’t remember enough from my statistics course to do that calculation. I see it as; if they fit a pattern then the pattern is highly likely to be correct.”

“I think that’s what I was trying to say,” replies Alan.

Pam says, “Let’s not speculate about the statistical theory we don’t know much about. Let’s talk about the legal approach, that’s where our skills lie.”

“You’re right, Pam. Probability and statistics have a place in the courtroom but they aren’t going to solve the Crawford case by themselves. Help me write up a brief paper summarizing what Mary has learned. As I thought last night, I want to take the summary to Judge Hopper. Now I know I want her to sign a warrant to search Squirrels residence, his motorcycle, and anything else he has that might have something that connects him to Martha. Is there anything you can suggest besides the obvious missing underwear?”

Mary replies, “Yes, the killer may have taken a gold signet ring Martha wore, although we don’t know if she was wearing it that day.”

“That’s good, Mary. Having two specific things may allow me to sneak in additional language broadening the search.”

An hour later Alan has a summary of the evidence he intends to take to Judge Hopper. Alan and Mary say goodbye to Pam and leave.

Chapter 15. An Exciting Dinner

 

When her guests arrive Thursday evening for dinner Pam can tell Mary’s excited. Everyone is ready to eat so Pam decides to wait until after dinner to ask Mary what’s excited her. After dinner and the table is cleared Eliza says, “Sarah, let’s you and I go look at Pam’s vegetable garden while the others talk about crime.” 

Sarah agrees and they go out to Pam’s garden. The others sit around Pam’s big dining room table. Pam says, “Mary, I can see you’re excited. What do the location runs say?”

“It’s really interesting. Remember the location runs that connected the robber Martha saw to the known check-cashing store robber? Those runs showed the robber spread his robberies all over metropolitan Detroit. That’s why he wasn’t identified. The robberies were each in different police jurisdictions. And the robber got enough money in each robbery to last him for three or four months. None of the police departments made the connection between the robbery in their area with the others across town. The last robbery yielded $25,000, enough to last him eight months or more if his spending habits continued as they apparently had between the earlier robberies. There were no robberies with his MO in over a year and a half after the one when he killed two people. That makes it look like he was lying low or he left the area,” Mary reports.

Pam interrupts, “MO, lying low. Mary, you’re using cop jargon.  You’re really getting into this police work.”

Everyone laughs, and then Pam continues, “Did you learn whether it’s likely he was lying low or left the area?”

“Yes, that’s what’s exciting. Comparing the timeline data to the location data shows he left the Detroit area, apparently right after the murders. And the location data shows a couple of hits along I-75 north and then lots in our area. The software indicates a 90% probability he’s in our area now and has been since he left the Detroit area.”

Sam and Peter yell with excitement. Sam says, “He’s our guy for sure.”

Peter says, “I agree, Sam. Do you agree, Pam?”

Always logical Pam replies, “Yes, I agree. This marvelous new AI tool points to Martha’s killer. But it doesn’t tell us his name, or address or what he is doing here. And more important, it gives us only circumstantial evidence. We need more to nail this killer.”

“Oh, I think we have more, Pam. That’s why I’m so excited. I’m pretty sure I know who he is,” says Mary.

“Tell us,” says Joe.

“Okay, I read his police record for his first robbery. The one he went to prison for. He worked as a tree trimmer before he went to prison. After prison, his parole officer reported he got his tree trimming job back. The parole officer also reported he was injured at work. He got a cut on his forehead requiring a lot of stitches. That may have left the scar Martha described to the police. The parole officer noted he climbed trees so well he had the nickname Squirrel. Having a job is probably why he seems to have lived so frugally. He used the money from his robberies to augment his pay as a tree trimmer.  Now, here’s where it gets exciting. The sheriff’s Crawford case file includes a report from Deputy Towner’s visit to Tommy’s Tree Trimming Tribe, the local tree trimming business with four T’s on their trucks. Two of Tommy’s employees were at the gift shop site trimming a tree the Saturday afternoon Martha was killed. One is Billy Red Deer and the other is called Squirrel. You can imagine how my heart raced when I read that.”

“Wow, we know who he is and where he works. Now we got him,” exclaims Peter.

“Yes and no,” says Pam. “We have a motive, maybe opportunity, and means, assuming if he’s strong enough to climb trees he’s strong enough to strangle Martha. We still need something to directly tie him to Martha to be certain he’ll be convicted. I don’t want to take another chance Judge Hopper dismisses this case. Squirrel would run for sure. Mary, what did the deputy’s report say about times? Could Squirrel have been there without any witnesses? ”

Mary replies, “The report quotes Billy Red Deer saying he left with their truck a little after 4:00. He saw Squirrel walking to his motorcycle and assumed Squirrel left. Oh, another piece of evidence, the killer Martha saw in Detroit left on a motorcycle, and Squirrel rides a motorcycle. And one more tidbit; Billy Red Deer said the gift shop was still open when they left because Squirrel went there to get a drink. I’m betting he recognized Martha, or Martha recognized him because of the scar on his forehead. I forgot to say earlier the police report on the killer Martha saw says Martha described a vivid scar on the killer’s forehead. While the last location run was in progress I called Deputy Towner and asked if Squirrel has a scar on his forehead. Unfortunately, he didn’t see Squirrel’s face.”

Peter interrupts, “I hear Sarah and Eliza coming. Don’t say anything about the rapist still being here. It’ll frighten Sarah. Let’s try to keep it quiet until Squirrel is locked up.”

Pam says, “We should keep it quiet, Peter. If Squirrel hears anything he’ll run again.”

The group stops talking while Sarah and Eliza come into the kitchen, get some ice tea, and go to the front porch. When they are out of hearing Sam says, “You did a great job, Mary. Now we need a plan for what we do next.”

Pam says, “I’ve been thinking about that all day. I’ve concluded we shouldn’t tell the sheriff just yet. He’s so impatient he might blow this opportunity. Let’s go to Alan Quick, the prosecutor, he’s more level headed. Alan and I are dating. I can see him without the sheriff knowing I’m involved in the Crawford case. I’ll arrange for Mary to present him with all the evidence we have. Maybe, with Alan’s help, we can figure out a plan to trap Squirrel or to find physical evidence tying him to Martha.”

“That sounds good to me, Pam. I say do it. Thank you for the wonderful dinner. I think we’ve accomplished what we wanted. I’m ready to get Sarah and go home,” says Peter.

“Me too,” says Sam.

Pam says, “Thank you all for coming tonight. I agree, we accomplished what we intended. I am hopeful Alan will help us finish the Crawford case.”

Chapter 14. Mary Needs Help

 

Mary Anderson gets a call at work on Thursday afternoon. It’s Peter; he says the Crawford’s signed the consent form and agreed to keep it quiet. Just before 5:00, she gets another call. It’s from Sam’s nephew, Jim. Jim gives her detailed instructions on how to access, input data, and run the AI-based algorithm remotely. It’s after her normal working time when she hangs up. She knows she has to do the search for Martha’s killer on her own time. She decided to start. First, she’ll do a simple case to verify she is using the algorithm properly. She runs the algorithm, without any of Martha’s data, using the State sex offender registry to see what the algorithm predicts for each of them for the time and place of Martha’s rape and murder. The algorithm predictions are what Sam said they might be. All of the probabilities are less than 1% except for Willie Sexton’s. It’s 4%, higher than any of the others, but not significant. Mary thinks, ‘With all his bumbling the sheriff did as good a job as possible given the information he had. Imagine how much effort he could have avoided if he had the use of this software.’ It’s nearly 9:00 when she finishes the first test and she’s hungry. She decides she’s done enough for the first day.

 

Friday after 5:00 Mary enters Martha Crawford’s data. She only has to input Martha’s name, address, schools attended, and job history. The AI program automatically matches her to the correct Martha Crawford on Facebook, Twitter, and Instagram, as well as to her bank accounts, her cell phone provider, all of her store credit cards, and loyalty cards. It even guesses correctly that she volunteered at Helping Hands and the gift shop. It didn’t guess at her being part of Doc Arra’s group. Mary is astonished but thinks, ‘At least it isn’t perfect. Maybe there’s still a role for us humans.’

Mary runs the algorithm again with Martha’s data. The result is the same. ‘I’m missing something,’ she thinks. She’s done enough for this night. She calls Pam. “Pam, this is Mary. Can you meet me for breakfast Saturday? I have run a couple of cases on the AI algorithm and the results aren’t helpful. I’d like your thoughts.”

Pam replies, “I have a better idea. Come out to my farm and have breakfast with me. We can talk freely here without worrying about people overhearing what we’re up to. Be here at 8:30, I’ll have coffee ready and breakfast on the stove.”

“Good idea. I’ll see you at 8:30. I’ll bring the printouts from the two cases I’ve run.” replies Mary.

 

Saturday morning after a quick breakfast Pam clears her antique dining room table while Mary spreads out the printouts she’s brought. When Pam sits down Mary says, “See, it’s just like Sam said it might be. All the probabilities are so low they are insignificant, even for Willie Sexton.”

Pam looks at the printouts and says, “Good to see the sheriff did as good as could be expected given the data he had.”

“That’s what I thought too, Pam. If he had this algorithm he could have avoided a lot of useless work,” replies Mary.

“I can see that, Mary. This algorithm has the potential to revolutionize police work even if it only eliminates useless work.”

“I think we’re missing something, Pam. That’s why I wanted you to see these results.”

 Pam says, “It’s telling us none of the known sex offenders is likely the killer. How about trying robbers? You looked at the medical examiner’s report. Is there anything suggesting it was a robbery made to look like a sex crime?”

Mary replies, “According to the Crawford case file Sheriff Ericsson considered robbery and rejected it. I can run the AI algorithm with robbers easily. I’ll go do that before lunch. Meet me for lunch at the Harbor Deli. I’ll have the results to show you. No one will know what we’re looking at.”

“‘Good idea, see you at noon at the Deli, says Pam.

 

Before they order lunch Mary puts the printout for robbers on the table for Pam to see. Pam looks at it, nods her head indicating she understands, and says, “I see. Let’s order and eat. I’ll think about these results. Only two men with probabilities greater than 4%. Did you check their backgrounds?”

Mary says, “Yes, they are both local low-level thieves with no history of violence. We’re still missing something.”

“Yes, it’s not sex connected, but it has to be connected to violence. If you’re willing to do another run today try known murderers.”

Mary says, “I can do that. I’ll call you later this afternoon with the results.”

 

Pam is cooking her dinner when Mary calls. Mary says, “I did a run with known murders from the State criminal database. The probabilities weren’t even as high as for the robbers. We’re still missing something.”

“I recall hearing a rumor that Willie Sexton had a vendetta with Martha’s father. Maybe that’s what accounted for his probability being four times higher than any other sex offender. What if we try unknown murders who may have encountered Martha at some time? They could have a fear of being identified?”

Mary replies, “Yes, the Crawford file says Willie has a vendetta with Martha’s father. Your idea is interesting. I don’t know how to set that up. I’ll call Jim. Maybe he can set it up for me. It may be Monday before I can connect with Jim. Have a good Sunday.”

 

Mary reaches Jim during her lunch hour on Monday. She explains what she wants to run. Jim says, “Yes, it can be done. I’ll have to make some coding changes.”

He calls Mary back at 5:00 and says, “I made the changes and ran the algorithm for unknown murders that might have a connection to Martha. It turns up a 60% probability for a connection to a check-cashing store killer Martha tried to ID when she lived in Detroit.  It didn’t ID the murderer.”

Mary says, “That’s good news, now we may be getting somewhere. Is there a way to adjust the algorithm to search for the check-cashing murderer?”

“I think so. Let me think about this. I am busy with another project I can’t delay. If I can think of how to set up the algorithm to search for that check-cashing store killer I’ll call you and tell you how to do it. It’ll be tomorrow.”

Mary calls Pam that evening and reports the progress. She tells Pam, “Now we know Martha had an encounter with a murderer. I'm getting hopeful now. Maybe Jim can tell me how to set up the algorithm to search for the identity of the murderer Martha encountered. I can hardly wait to hear from Jim.”

 

At noon on Tuesday Jim calls Mary. He tells her how to set up the algorithm to try another approach first. She’s to set it to look for the check-cashing store robbers in past data who may or may not have killed anyone.”

 After 5:00 Mary makes the adjustments Jim explained. She runs the algorithm and finds a series of check-cashing store robberies in the metropolitan Detroit area. The first occurred ten years earlier. That robber was caught and served five years. There’s four more after he’s let out, the last one being the only one with murders. There’s an 85% probability the known robber did the other robberies. The algorithm reaches that conclusion based on the AI analysis of the known robber's social behavior and location data. It is late by the time Mary gets those results. She quits for the day. As soon as she gets home she calls Pam. She says, “Pam, I’ve got great news. The latest run shows an 85% probability a known check-cashing store robber is the same one Martha encountered. A few more runs with different parameters should give us a clearer picture. I’ll call again tomorrow night after I make more runs.”

Pam says, “This is getting exciting. Can I join you at 5:00? Maybe you can complete a run or two before we go to the museum for our Wednesday session.”

“Yes, that’s okay. I’ll take my lunch tomorrow. I can set up another run while I’m on my lunch hour.”

 

Mary is ready for the next run when Pam joins her at 5:00. Mary says, “I set up a run to ask the probability the known robber who murdered people on his last robbery; at least there’s an 85% probability he’s the same one, would kill Martha to avoid being identified and convicted of murder. Let’s run it and see what it says.”

Pam and Mary pace the room and chat waiting for the run to finish. It takes an hour. They hover over the computer screen when the run finishes. Mary says, “Look, it says there’s a 75% probability the known robber would kill to avoid being convicted of murder. I think we have our man if there’s any way he would have been in Pineville on the day Martha was killed. I can run the location cases tomorrow night.”

Pam asks, “Can it tell us the probability this man would rape his victim or make it look like rape to throw suspicion on a sex offender?”

Mary replies, “I’m sure Jim can tell me how to set that up. First, though, I want to run the locations. I know how to do that. Let’s go to the museum and tell Joe, Sam, and Peter what we have learned since last week. I’ll make the location run tomorrow night.”

 

Pam and Mary go to the museum where Joe, Peter, and Sam are waiting anxiously to hear what Mary has accomplished. She tells them step by step what she did and what results she got.

When she finishes Sam says, “Great job, Mary. That artificial intelligence-based algorithm is working like Jim hopes. If it connects that known robber and murderer to Pineville then he’s Martha’s killer.”

“I’ll know the probability he could have been in Pineville tomorrow night by 6:00,” says Mary.

Pam says, “With an 85% probability the known robber is the man who robbed the check-cashing store and killed two people I am surprised it’s only a 60% probability he’s the one Martha saw but couldn’t identify.”

“Jim says we shouldn’t expect probabilities to match like that, Pam. It’s because the AI algorithm may weigh social and psychological factors differently for different runs. What counts is the two probabilities are statistically significant, which they are,” Sam explains.

“Thank you for explaining that, Sam. I think that means he’s the same guy and he’d kill Martha to stop from being convicted of murder. I conclude he has a motive. Since the software isn’t perfect yet I think we have identified Martha’s killer even if the software doesn’t tie him to Pineville. Mary, can you look up this man’s background? Maybe one of us can tie him to Pineville if he’s been in the area recently.”

Mary replies, “Yes, I can read his police file while the location run is underway.”

Joe asks, “What are we going to do if we conclude we’ve identified Martha’s killer?

“Good question, Joe. I don’t think going to the sheriff is the right thing. He is liable to move too quickly and screw things up. How about this? Let’s meet at my farm tomorrow night at 6:30. I’ll have dinner ready for us and Mary will have the location run data and the known information on the suspect,” says Pam.

Sam says, “Yes, let's do that. I don’t want to wait until next Wednesday to plan our next step. Thanks for the dinner offer, Pam.”

Peter says, “Pam, would you mind if Sarah comes with me? She’s not as fearful as she was but I’d still not like to leave her alone at night.”

“Of course not, Peter. I’ll have plenty. My garden is near its peak. Be ready to eat a lot of veggies. Joe, you bring Eliza too.”

“I’ll bring dessert,” Sam offers.

“Sarah will love the opportunity to show off her bread-making skills. We’ll bring bread,” Peter says.

“I’ll be in trouble with Eliza if I don’t offer to bring something. How about we bring appetizers?” says Joe.

“You’re all making this easy for me,” Pam says. “Let’s go home. I’ll lock up tonight.”