OCR AAQ Applied Science • F185 • Lesson 7 • Task 1 preparation

Fingerprints and Shoeprints

Pattern evidence: identify the features, record them properly and separate useful comparison from overconfident claims.

By the end

You should be able to…

  • recognise arch, loop and whorl fingerprint pattern groups
  • explain why broad pattern type is not unique identification
  • describe useful shoeprint features including tread and wear
  • write a reasoned questioned-reference comparison
Are two loop fingerprints automatically from the same finger?
Physical evidence

What features can we compare?

Click each information panel. It opens straight to the information — no extra reveal.

🌀Fingerprint patternsArch, loop and whorl are broad pattern groups.Click for information
🔎Ridge characteristicsFiner ridge features make comparisons more discriminating.Click for information
👟Shoeprint featuresSize, tread design, wear, cuts and damage.Click for information
📷Evidence qualityPartial, smudged or distorted prints reduce confidence.Click for information
ArchLoopWhorl

Pattern ≠ identity

Many people have loops, whorls or arches. Broad pattern is useful for classification, but finer ridge characteristics and print quality matter for stronger comparison.

A shoeprint has a common tread but a distinctive cut. Which may be more discriminating?
Teacher model

Comparing a partial shoeprint

Questioned print: size about 9, zig-zag tread, triangular logo area and a missing tread block on the outer heel. Reference A shares all four; B shares size/tread but has an intact heel.

Why should the missing heel block be recorded?
Guided practice

Pattern, detail and evidence quality

Press start

Work through the cases one at a time.

These are parallel practice examples, not the live set assignment.

Independent consolidation

Print Comparison Challenge

Fingerprint: Questioned print is a loop with a ridge ending and bifurcation near the core. Ref A is a loop with both features in comparable positions; Ref B is a loop but lacks the bifurcation.

Shoeprint: Questioned print is 28 cm long, wave tread, with a diagonal cut on the outer heel. Ref C matches; Ref D has the same tread but no cut.

  1. Which references are more consistent?
  2. Explain why broad class features alone are weaker than multiple details.

Review notes

  • Fingerprint broad pattern groups include arches, loops and whorls.
  • Broad pattern type alone is class-level information; finer ridge characteristics and quality make comparison more discriminating.
  • Shoeprints can be compared using size, tread pattern, logos, wear, cuts and damage.
  • Distinctive acquired wear/damage may be more discriminating than common manufacturer tread.
  • Photograph and record impressions clearly, with scale where appropriate, before recovery.
  • Partial, smudged or distorted prints reduce confidence.

Glossary

Why this matters for Task 1

P2/M1 requires students to plan documentation/recovery of print evidence. P3/M2 requires an appropriate comparison method and explanation of why it suits the evidence.

Final checkpoint

Lesson 7 quiz