Opinion Evidence

Question 1

What is the general rule against opinion evidence?

Answer 1

Witnesses should only testify as to facts within their personal knowledge and not given an opinion on the disputed issues. Determination of issues is the preserve of the jury.

2 qualifications to the rule:

• Non-expert opinion evidence
• Experts in specialised fields

Question 2

In Sherrard v Jacob 1965, what did Lord MacDermott CJ list as examples as to when non-expert opinion can be given?

Answer 2

1. ID of people and things
2. Apparent age of someone
3. Bodily plight or condition of a person
4. Emotional state of a person
5. Condition of things
6. Certain questions of value
7. Estimates of speed and value
8. Handwriting

Question 3

What is the considered when admissing expert evidence?

Answer 3

1. Assistance
2. Expertise
3. Impartiality
4. Reliability

Question 4

How may an expert provide assistance to the court?

Answer 4

An expert may give evidence on matters outside general knowledge and understanding of the jury.

This is decided through the TURNER 1975 test.

Question 5

What areas may there be a need for an expert?

Answer 5

• Physical/abnormal mental illnesses
• Sciences
• Technology
• Engineering
• Foreign Law
• Business practices
• Art
• The way children think.

Question 6

With mental illnesses, when is an expert required?

Answer 6

Masih 1986:

There is no definitive line separating extreme emotions from mild mental illnesses or the mentally normal from the mentally subnormal, but in order to preserve questions of facts for jury, an arbitrary line has been drawn at an IQ of 70

Question 7

What makes someone an expert?

Answer 7

To classify as an expert, the individual must be properly qualified in the subject calling for expertise.

It is the expertise itself which determines a witness’s competence and not the route by which he came to have it.

It is not always necessary to have formal qualifications

Sometimes decided by holding a voir dire if disputed.

Question 8

In the Law Commission’s proposal, what is the new test for expertise?

Answer 8

Clause 2:

1. For purposes of section(1)(1)(b), a person may be qualified to give expert evidence by virtue of study, training, experience or any other appropriate means.
2. The court must be satisfied on the balance of probabilities that the person is so qualified.

Question 9

Why must an expert be impartial?

Answer 9

Rule 19.2 CPR 2015:

1. An expert must help the court to achieve the overriding objective-
   
   1. by giving opinion which is-
      
      1. objective and unbiased
2. This duty overrides any obligation to the person from whom the expert receives instructions or by whom the expert is paid.

Question 10

As specified in the Law Commission’s guide, what is the new test for impartiality?

Answer 10

Clause 3:

1. An expert has duty to the court to give objective/unbiased expert evidence for the purpose of criminal proceedings.
2. That duty overrides any obligation to any person whom the expert receives instructions or by whom the expert is paid.
3. If appears to court that there is a risk that the expert will not comply with that duty, the expert evidence is not admissible unless court is satisfied in interests of justice that it should be admitted.

Question 11

Why should the expert evidence be reliable?

Answer 11

There should be a sufficiently reliable scientific basis for the expert evidence or it must be part of a body of knowledge or experience which is sufficiently organised/recognised to be accepted as a reliable body of knowledge or experience.

Question 12

What are the three different approaches taken by the Court of Appeal when determining reliability?

Answer 12

1. Liberal Pragmatism - field of expertise must be “sufficiently well established to pass ordinary tests of relevance and reliability.” Dallagher
2. Opinion forms part of a body of knowledge or experience Bonython
3. General Acceptance test: for an expert to give an opinion based on scientific theory, that theory “must be sufficiently established to have gained general acceptance in the particular field in which it belongs” Gilfoyle

Question 13

What is the Law Commission’s Reliability test?

Answer 13

Clause 4(1) Test of Reliability:

1. Expert opinion evidence is sufficiently reliable to be admitted if -
   
   1. The opinion is soundly based, and
   2. The strength of the opinion is warranted having regard to the grounds on which it is based

Question 14

Can an expert give evidence on the ultimate issue?

With what weight must the expert evidence carry?

Answer 14

• The expert may be called to give an opinion on an ultimate issue
  
  • Pora v R 2015
• Weight:
  
  • Expert evidence should be treated like evidence of any other witness - determined by jury.
  • Fitzpatrick 1999 - jury are not bound by expert opinion
  • Brennan 2014- if evidence is uncontradicted, jury should accept it.

Question 15

What is the hearsay exception specifically for expert opinion?

Answer 15

CJA 1988 S30:

1. An expert report shall be admissible as evidence, whether or not the person making it attends to give oral evidence in those proceedings.
2. If proposed that the person making the report shall not give oral evidence, the report shall only be admissible with leave of the court.

This applies to statements of fact and opinion.

Question 16

When is finger mark evidence admissible in court?

Answer 16

• A person may be ID by their fingerprints alone without need for supporting evidence.

Buckley 1999:

• < 8 matching ridge characteristics = highly unlikely to be admissible.
• 8 or more = Judge may/may not exercise discretion to admit
• Palm and plantar analysis should be approached in same manner.

Question 17

Is ear print evidence admissible?

Answer 17

• An ear print can be taken from a suspect on arrest and compared with marks found at scene
• Dallagher 2002: evidence of a suitably qualified expert is admissible in forming a conclusion as to whether the print and marks match.
• Kempster 2008: Ear mark comparison capable of providing information that could ID a person who had left ear mark on a surface, but can only be done when minutiae of ear can be identified.

Question 18

Is facial mapping evidence admissible?

Answer 18

• A person may be identified by facial mapping techniques
• Grey 2003: Facial imaging or mapping is admissible to demonstrate particular facial characteristics or combinations of such characteristics.
• Atkins and Atkins 2010: must be made clear to jury that such expert evidence (a) is an expression of subjective opinion and (b) is not based upon comparison with statistical database recording incidence of features compared as they appear in population at large.

Question 19

Is Lip Reading Evidence admissible?

Answer 19

• Lip reading evidence from a video is potentially admissible in evidence.
• Luttrell 2014: Lip reading undertaken by a suitably qualified lip reader was a well-recognised skill and part of a reliable body of knowledge and opinion.

Question 20

Is DNA evidence admissible?

Answer 20

• DNA profiles from crime samples can be compared against profiles on the NDNADB in order to seek to identify thre offender
• Relationship of DNA profile to that of suspect is known as the match probability.
  
  • Lashley 2000 - positive match between crime sample and suspect may require supporting evidence.
  • Darnley 2012 - Claim that DNA had been left on moveable object innocently and left at scene by someone else required supporting evidence.

Question 21

What is the Prosecutor’s Fallacy, as described in Doheny; Adams 1997?

Answer 21

“It is easy to draw the following conclusion:

1. Only one in a million will have a DNA profile which matches that of the crime stain
2. The D has a profile which matches the crime stain
3. Ergo there is a million-to-one probability that the D left the stain and is guilty of the crime.
4. This reasoning is fallacious and is the “Prosecutor’s Fallacy”

C 2011 - PF is not always enough in declaring conviction unsafe