Ethics of the scene
Debate whether investigators should be allowed to alter a scene to collect evidence, and defend your view.
Written CER (3-5 sentences) taking a side on whether investigators should disturb a scene to collect evidence, with a chain-of-custody reference in the reasoning.
- 1Do thisDebate whether investigators should be allowed to alter a scene to collect evidence, and defend your view.
- 2Use this resource
- 3Submit thisCER: Written CER (3-5 sentences) taking a side on whether investigators should disturb a scene to collect evidence, with a chain-of-custody reference in the reasoning.
- 4Submit it here
- 1CMSD website. Go to clevelandmetroschools.org and click the Clever button.
- 2Clever. Clever opens. Sign in if it asks.
- 3Microsoft (district) login. Use your district Microsoft account (the one for school).
- 4Schoology. Open Schoology, then your class, then Assignments, and find the file named below.
The file to submit is named: Principles of Biomedical Technology (Principles of Biomedical Science) › Unit 1.1 Investigating the Scene: Forensic scene documentation, evidence log, crime-scene sketch, trace evidence, biometric data. › CEROpen Schoology
What counts as evidence, and where to find it
What makes evidence strong, and where do you find evidence you can trust?
Evidence is the data and observations you use to back up a claim. In science that means measurements, experimental results, images, and records, not “my friend said” or “I saw it once.”
Strong evidence is relevant (it actually bears on the claim), sufficient (there is enough of it), and reliable (it was collected carefully and others could repeat it). One data point is rarely enough; a pattern across many is far stronger.
Where you find it matters. Prefer primary sources and reputable ones: peer-reviewed studies, government and health agencies (CDC, NIH, NHGRI), and your own lab data. When you find a source online, do not trust it on looks. Check who is behind it and what better sources say.
- • Relevant: it directly supports (or tests) the claim.
- • Sufficient: there is enough of it, not a single lucky data point.
- • Reliable: collected carefully, and others could reproduce it.
- • Sourced: you can say where it came from and why that source is trustworthy.
- • Stop. Investigate the source: who made this and why?
- • Find better coverage: what do other reputable sources say?
- • Trace claims and quotes back to the original.
Find two pieces of evidence for a claim in this unit, one from your lab/class data and one from a reputable source. Note why each source can be trusted.
Read to prepare for today
Vetted sources picked for today's question. Skim these before you take a position or start the work, so your argument and evidence are grounded.
- CER:
- Claim, Evidence, Reasoning — make a claim, back it with evidence, explain your reasoning.
- SOP:
- Standard Operating Procedure — the exact steps to follow (especially in a lab).
- Tracker:
- Your PLTW progress log where you record completed evidence.
- myPLTW:
- The PLTW course site where you do the online activities — you open it through Schoology.
Minute-by-minute · 80-minute block
💡 Big idea: How you handle a scene determines whether the evidence collected from it can ever be trusted.
- 0:00Hook: short description of a famous case where scene contamination threw out key evidence
- 0:08Introduce chain-of-custody concept; students define it in their own words
- 0:18Read the ethics prompt; list one cost and one benefit of disturbing a scene
- 0:30Small-group debate: pick a side, argue with one reason grounded in chain of custody
- 0:52Individual CER writing: position, one piece of evidence, one reasoning sentence
- 1:10Share two CERs; preview Tuesday scene-documentation content
- • Imagine you are the first person on the scene of a suspicious death. What is the first thing you do? If you touch anything before documenting it, you may just have destroyed the best evidence.
- • Today's question is a genuine ethical dilemma that real investigators face: when does collecting evidence cross the line into destroying it?
- • The legal concept of chain of custody means that every piece of evidence has a paper trail from the moment it is found. Break the chain and a lawyer can throw the evidence out entirely.
- • Your job today is to pick a side and defend it with reasoning. There is no easy answer, and that is the point.
- 1Read the prompt: When does collecting evidence cross into destroying it?
- 2List one cost and one benefit of disturbing a scene to gather trace evidence.
- 3Choose a side: preserve untouched vs. collect aggressively.
- 4Argue your claim in your group with one reason grounded in chain of custody.
- 5Post a written CER stating your position and one piece of supporting evidence.
- • I can connect scene handling to chain-of-custody integrity.
- • I can defend a claim with a reason and an example.
- • Chain of custody is the documented record showing who handled evidence, when, and how, from collection to courtroom.
- • Disturbing a scene without documentation can contaminate or destroy trace evidence, rendering it inadmissible.
- • Every collection decision involves a tradeoff between preserving context and obtaining a sample.
Your PLTW work today
Unit 1.1 Investigating the Scene: Forensic scene documentation, evidence log, crime-scene sketch, trace evidence, biometric data. · Ethics of the scene
Day 1 of this lesson. Open this exact section in myPLTW (reached through Schoology), then do the work below.
Do this: Log in to myPLTW and open the Lesson 1.1 Investigating the Scene unit. Read the unit overview so you understand the case and chain-of-custody framework before Tuesday.
Mark the Lesson 1.1 overview reading complete in myPLTW.
You finished the course launch last week. Today starts Lesson 1.1. The overview reading should be done by the end of this block.
myPLTW progress screenshot showing the Lesson 1.1 overview task marked complete.
All PLTW activities are completed inside the PLTW course environment — this page only gives direction. Submit producibles on Schoology.
Today's PLTW tracker
Check things off as you work, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible on Schoology.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
Unit 1.1 Investigating the Scene: Forensic scene documentation, evidence log, crime-scene sketch, trace evidence, biometric data. · Ethics of the scene
Log in to myPLTW and open the Lesson 1.1 Investigating the Scene unit. Read the unit overview so you understand the case and chain-of-custody framework before Tuesday.
You finished the course launch last week. Today starts Lesson 1.1. The overview reading should be done by the end of this block.
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Debate whether investigators should be allowed to alter a scene to collect evidence, and defend your view.
- Read the prompt: When does collecting evidence cross into destroying it?
- List one cost and one benefit of disturbing a scene to gather trace evidence.
- Choose a side: preserve untouched vs. collect aggressively.
- Argue your claim in your group with one reason grounded in chain of custody.
- Post a written CER stating your position and one piece of supporting evidence.
CER: Written CER (3-5 sentences) taking a side on whether investigators should disturb a scene to collect evidence, with a chain-of-custody reference in the reasoning.
Submit on SchoologyUpload by 11:29 PM for full credit.
| Task | Who |
|---|---|
| Read the prompt: When does collecting evidence cross into destroying it? | _______ |
| List one cost and one benefit of disturbing a scene to gather trace evidence. | _______ |
| Choose a side: preserve untouched vs. collect aggressively. | _______ |
| Argue your claim in your group with one reason grounded in chain of custody. | _______ |
| Post a written CER stating your position and one piece of supporting evidence. | _______ |
Working solo? Put your own name in "Who" for every row.
- I can connect scene handling to chain-of-custody integrity.
- I can defend a claim with a reason and an example.
Resources & readings
Hand-picked materials for this lesson. Class file items open the document directly; the rest are vetted readings and interactives from other biomedical programs.
Lab & supplies
WebXam practice
Cumulative WebXam review
A quick mixed-review pulling questions from earlier units plus today, so the WebXam material stays fresh.
Where this leads — careers
What today's skills lead to. These are real health-science careers this course builds toward. Tap one to see, on the US Department of Labor's O*NET site, what the job actually involves, what it pays, and how fast it is growing.
What to do if you were absent
Watch the recorded scene-ethics prompt and post your written CER taking a side on whether disturbing a scene is justified.
John Carroll Philosophy for ChildrenThen submit your CER on Schoology.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
Khan Academy: using the microscope (Cell biology)- CompleteEvery required part of the artifact is present, nothing left blank.
- AccurateThe science and the data are correct and match the evidence.
- Scientific reasoningYou explain your claim with evidence and reasoning (CER), not just an answer.
- Professional communicationClear, organized, labeled, and written the way a clinician or scientist would.
- SubmittedTurned in the right way (Schoology for routine work) and confirmed.
Drop your Mon, Aug 31, 2026 · Ethics of the scene here. Use a clear file name (your initials + project). Routine work still goes to Schoology (via the CMSD portal).
Upload a project