The Detective’s DeskAva Hart
Other swimmer
What happened from your point of view?
I used locker 72, not 27.
What should I check to test that account?
My key is still on my wrist band.
EASY · CASE FILE
A Key in the Return Slot
Easy · A community swimming pool
A key is reported stolen. Follow its number and the return-slot mechanism before accusing another swimmer.
Read the case file below, or open the interactive desk to examine records, keep notes and submit your reasoning. These are the case materials, without the solution.
The scene
Locker 27 is locked and contains all of its owner’s belongings. The key return box is opened with staff present.
People and accounts
Ilan Vale
Swimmer
What happened from your point of view?
My key vanished after I visited the café hatch.
What should I check to test that account?
I put my café token into the return slot beside it.
Ruth Moss
Pool attendant
What happened from your point of view?
Keys and tokens have different shapes.
What should I check to test that account?
Our locked return box keeps every object dropped into it.
Case records
Read each record on its own terms. A claim made by a person is different from a fact established by an independent record.
Case record · Locker corridor
Token in the towel
Ilan’s unused café token is folded into his towel; it was not returned.
Case record · Pool desk
Other swimmer’s key
Ava carries key 72 on her own intact band; it does not open locker 27.
Case record · Locker corridor
Locker check
Locker 27 is intact, locked and contains the complete item list Ilan supplies.
Case record · Pool desk
Return box contents
The supervised opening finds key 27 attached to Ilan’s band, among café tokens.
Questions to resolve
Where did key 27 go?
Who is established as a key thief?
Use the interactive case desk to select your finding and cite the records that support it. The answer is checked there, and your progress stays in your browser.
Build your finding
Compare the records with each account. Work out what the evidence establishes, then separate that finding from anything it does not prove.