WRITE UP MODEL
WJEC LEVEL 3 APPLIED DIPLOMA IN
CRIMINOLOGY
AC 3.1: Examine Information for Validity
Introduction
In the criminal justice system, decisions to prosecute must be based on information that is
valid and trustworthy. The Crown Prosecution Service (CPS) applies strict standards to
ensure that evidence relied upon in court is credible, reliable, and admissible. Examining
information for validity is essential to prevent miscarriages of justice and to ensure fair trials.
This section explores the validity of evidence, including eyewitness and expert testimony, as
well as the use of trial transcripts, supported by relevant case examples.
Evidence: Credibility, Reliability, and Admissibility
, Before proceeding with a prosecution, the CPS requires that evidence meets three key
criteria:
Credible evidence refers to information that is believable and plausible within the context of
the case. It should make logical sense and align with known facts.
Reliable evidence is accurate, authentic, and consistent. Reliable evidence remains stable
when examined across time and different sources, showing minimal contradiction.
Admissible evidence is evidence that is legally acceptable in court. It must comply with
legal rules and procedures, meaning it has been obtained lawfully and fairly and can be
presented to the court as part of the official body of evidence.
Only when evidence satisfies all three criteria can it be considered valid for use in criminal
proceedings.
Testimonies as Evidence
Testimonies are a common form of evidence and can be divided into eyewitness testimonies
(EWTs) and expert or specialist testimonies.
Eyewitness Testimonies (EWTs)
Eyewitness testimonies come from individuals who claim to have observed a crime. While
they can be valuable, their validity is often questioned due to psychological research
highlighting issues with human memory.
Loftus’ research into memory demonstrated the phenomenon of weapon focus, where
witnesses to crimes involving weapons tend to focus their attention on the weapon rather than
other details, such as the offender’s face. This can reduce the reliability of eyewitness
accounts.
However, EWTs are not entirely invalid. They can provide police with investigative leads,
even if details are not completely accurate. Their reliability can be improved through
effective interviewing techniques, such as the cognitive interview, which helps witnesses
retrieve memories more accurately by reinstating context and reducing leading questions.
In court, eyewitness testimonies can carry significant weight, particularly when they
corroborate other forms of evidence. When supported by physical or forensic evidence,
EWTs may be considered sufficiently reliable to contribute to a verdict.