"It must have been the old lady who did it, because they moult a lot." It's unlikely, you would hope anyway, that this conclusion has ever been reached before in a criminal investigation. But with some of the "Forensic Rookies" who are trying to solve a mysterious Scottish whodunit still in P1, the occasional unusual hypothesis is understandable.
That said, the "elderly women shed more hair" theory is actually proposed - apparently semi-seriously - by a 12-year-old pupil at Inveralmond Community High in Livingston.
The West Lothian school is among nine primaries and secondaries across Scotland working together to find out who committed a robbery at an art gallery.
There are three named suspects - Danielle, who works at the next-door pet shop, Eric, an out-of-work ex-con seen loitering outside at the time of the theft, and Anne, the "elderly" cleaner who was the last to see the painting before it was stolen. One unidentified suspect is also mentioned.
It is clear from some of the discussion threads on Glow, the national schools intranet, that the fictional case caught pupils' imaginations. Over the past six weeks, they have used scientific techniques to analyse fingerprints, footprints, "blood" spatters, teeth imprints (in chewing gum found at the scene) and hair samples - identifying strands of cat, dog and also human origin, which raises their suspicions about Anne.
One name in the debate, which may sound familiar, is Xanthe Mallett. A real-life Scottish forensics expert, she stars in the BBC hit series History Cold Case. Dr Mallett agreed to take part in the project to improve links between schools and scientists and boost children's interest in science by tapping into the popularity of TV crime programmes.
She thought the pupils were excellent as forensic experts. "They asked pertinent, intelligent questions, and noticed all of the key pieces of evidence. They were inquiring and showed real flare for investigation," she says.
"Pupils seeing other pupils having such a great time, which they obviously did, should help encourage more to participate. If we can just show them what you really do with science, then we have a chance to inspire them and really make learning fun and science cool."
All good crime series need a decent theme tune, and at Urafirth Primary in Shetland, The Who's Who are You? plays at the start of their investigation.
Headteacher Wilma Missenden, whose class spans P1-7, says: "It's been great. I was surprised by how much the human story caught their eye. At the beginning, we talked about stereotyping and I told them to keep an open mind about Eric, but I was still very surprised that they did not all say it must have been him.
"They have been down on their hands and knees measuring `blood' spatters. It got their thinking skills well and truly pumping!"
Project creator Susan Rodrigues, a Northumbria University academic specialising in science education, agrees: "I didn't expect them to treat it quite so realistically! At first, they were very accepting of authority, but soon they were challenging answers."
Another aim of the project was to ease the often difficult transition from primary to secondary school for pupils, which Professor Rodrigues says worked well in Shetland: "The communication between primary and secondary there started quite formally and became very chatty."
Meanwhile, a final aim of increasing ICT use, with pupils creating wiki sites to outline their findings on Glow, also worked well - until today's meet, when unfortunately no one is able to solve the mystery of why Inveralmond's sleuths can't hear anyone else.
Waiting for the problems to be resolved, Emma Walker, 12, enthuses about the practical work with science teacher Diane McMichael.
"We took our own fingerprints, checking for whorls, loops and arches and we analysed hair samples under a microscope and found a mixture of cat, dog and human hair," she says.
For a time the connection works, so Emma speaks into the microphone to explain that, based on the hair analysis and the suspects' behaviour during filmed "police interviews", her class believes Danielle and Eric were in cahoots.
They are almost right, as it is revealed that Danielle is indeed the culprit. Poor Eric is innocent, however.
At Coupar Angus Primary in Perth and Kinross, pupils get so into their role that they all dress in white CSI suits for the Glow meet. And they are so outraged by perceived police harassment of Eric during his "interview" that they have started a campaign to highlight discrimination against the former prisoner.
Headteacher Margaret Cameron says: "It certainly was a highly motivating project and developed into something much bigger than we had initially thought it would be.
"They all want to be forensic scientists now."
Shetland teachers are keen to expand it in future to include all feeder primaries. If they do, Dr Mallett has already asked to continue her starring role alongside pupils.
The project was funded through the Astrazenica Science Teaching Trust
INQUIRY OF THE PUPIL DETECTIVES
Pupils' questions and conclusions:
"She was awfully cheery and happy for someone being interviewed by the police, so it could be a front. Her facial expressions didn't seem to match her responses."
"Did the security guard have a security dog? This could mean that the animal hair was left by it and not the thief."
"We thought it was suspect one, but now we are confused because suspect four's fingerprint has the right arch and loop in the middle."