Concordance Criterion
Definition
The minimum degree of pattern agreement required before an examiner can report a positive identification. For lip prints, no consensus criterion exists, which is a core criticism of the technique's evidential reliability.
- Function
- Minimum pattern agreement for positive identification
- Status for lip prints
- No consensus criterion exists
- Consequence
- Core criticism of cheiloscopy reliability
- Field
- Cheiloscopy
Common questions
Why is the absence of an agreed concordance criterion such a significant weakness for lip print evidence?+
Without an established minimum number or type of matching features, different examiners can reach different identification conclusions from the same comparison, and there is no validated statistic showing how often a given level of agreement occurs by chance. This makes it difficult to express the strength of a lip print match in the way fingerprint or DNA evidence can be.
How does this compare to fields like fingerprint examination, which also lack a single universal numeric threshold?+
Fingerprint examination in many jurisdictions has moved toward documented, validated methodologies and proficiency testing even without a single fixed minimum point count, whereas lip print comparison lacks comparable large-scale validation studies establishing error rates, which is why courts and forensic bodies treat cheiloscopy conclusions with more caution.
Related terms
- Cheiloscopy
- Study of lip prints (Greek cheilos, lip; skopein, to examine). The furrow system on human lips was first described by anthropologist R....
- Latent Lip Print
- A lip print deposited without lipstick or coloured product, invisible to the eye and requiring chemical or physical development before comparison. Composed...
- Lip Print Persistence
- The duration over which a deposited lip print remains retrievable from a surface. Affected by surface material, environmental conditions, handling of the...
- Suzuki-Tsuchihashi Classification
- The 1970 system that divides lip groove patterns into five main types (I, I', II, III, IV, V) based on groove direction,...
- Vermilion Border
- The reddened transition zone between the facial skin and the labial mucosa. It is covered by a thin, partly transparent mucosa that...