ENFSI Guidelines for Evaluative Reporting

Question 1

What is an evaluative report?

Answer 1

An evaluative report is any forensic report containing an evaluative reporting section.

It provides an assessment of the strength to be attached to the findings in the context of alleged circumstances.

Question 2

What are the four types of forensic reporting?

Answer 2

1. Evaluative
2. Intelligence
3. Investigative
4. Technical

Question 3

What is a simple description of a likelihood ratio?

Answer 3

The strength of support the findings provide to discriminate between propositions of interest.

Question 4

What is probability as a measure of uncertainty based upon?

Answer 4

• The findings of the case
• Associated data
• Expert knowledge of the field
• Case specific propositions
• Conditioning information.

Question 5

What different pieces of information should be in an evaluative report?

Answer 5

• The conditioning information used
• The propositions of interest.
• Relevant items collected and received.
• Items examined.
• Significant findings obtained.
• Discussion and evaluation of the findings.
• Conclusions

Question 6

What should evaluative reports address, and how is the conditional transposed?

Answer 6

• Evaluative reports should address the probability of the findings, given the propositions and relevant background information.

NOT

• The probability of the propositions given the findings and background information.

Question 7

What conditions affect evidence transfer?

Answer 7

• The pressure applied during contact
• The number of contacts
• How easily the item transfers material.
• The form of the evidence (solids, liquids etc.)
• How much of the item is involved in the contact.

Question 8

What are the different mechanisms of transfer?

Answer 8

Direct transfer is where the evidence is transferred from the source to a location, with no intermediaries (primary transfer).

• Straightforward to interpret

Indirect transfer is where the evidence is transferred from the source to a location via one (secondary) or more (tertiary) intermediate.

• More challenging to interpret and potentially misleading.

Question 9

What is the ‘persistence’?

Answer 9

Once evidence transfers, it will persist on the location until further transfers, degrades until it is unusable/unrecognisable, or is collected as evidence.

Question 10

What determines the persistence?

Answer 10

1. The type of evidence
2. The location of the evidence
3. The environment around the evidence
4. The time from transfer to collection
5. Activity of or around the evidence location.

Question 11

What evidence is reported categorically, and what evidence is reported evaluatively?

Answer 11

Categorical: Fingerprints and drug test data, handwriting, tool marks etc.

Evaluative: DNA, Fibres, Medico/legal discussions