The role of computer evidence in the criminal justice system will
be examined through a call for evidence launched today [Tuesday
21 January] to prevent future miscarriages of justice.
Currently, there is a presumption that computers work correctly
and any evidence generated by software is accurate, unless there
is evidence to the contrary.
However, the limitations of this were highlighted by the wrongful
convictions of hundreds of innocent sub-postmasters in the Post
Office Horizon scandal. Faults in the Post Office's accounting
software system proved the fallibility of digital evidence and
the potential for devastating miscarriages of justice if evidence
is not thoroughly interrogated.
The 12-week call for evidence will invite views from across the
justice system and beyond on the presumption.
By seeking new ways to ensure people are better protected from
miscarriages of justice, this expert review will help to build on
the government's broader efforts restore public confidence in
policing and in the criminal justice system through our Plan for
Change.
Justice Minister KC said:
“We must learn the lessons of the Post Office scandal. A blanket
‘no questions asked' acceptance of the accuracy of digital
evidence can have a devasting impact on people's lives.
“We need to carefully consider how we can both use and
interrogate digital evidence in court. Ensuring people are
protected from miscarriages of justice is vital, and one part of
the government's Plan for Change.”
Computer evidence forms a substantial part of many modern
prosecutions, particularly in crimes such as fraud, which can
involve thousands of digital documents. Digital evidence is also
often used in rape and serious sexual offence cases.
Any change requiring the prosecution to prove any computer device
works ‘correctly' could impact how quickly cases can be
completed. Therefore, any reform must be well thought out and
future proofed.
The call for evidence is seeking expert input on how computer
evidence should be defined, and what could fall into scope of any
change to the law. For example, distinctions might need to be
drawn between general digital evidence like text messages or
social media posts, and evidence which has been specifically
generated by a computer system or software.
It will seek views from organisations and individuals with
experience of the criminal justice system, along with those with
expertise in computers and software.
The miscarriages of justice which occurred in the Post Office
cases were down to deliberate failures to properly interrogate
and disclose evidence - which prevented postmasters and others
from effectively challenging the reliability of the Horizon
computer system evidence.
Any changes to the presumption would not be able to further
protect against instances where parties mislead a court on the
accuracy of the evidence. But lying in court – or perjury - is a
separate crime already.
However, removing or changing this presumption could mean
defendants are better equipped to interrogate computer evidence
against them, and would put more onus on the party supplying the
digital evidence to ensure it can stand up to scrutiny.
ENDS
Notes to editors:
- Find the Call for Evidence here: https://www.gov.uk/government/calls-for-evidence/use-of-evidence-generated-by-software-in-criminal-proceedings
- In 2000, section 69 of the Police and Criminal Evidence Act
1984, which covered the use of evidence from computers, was
repealed. Prior to this, it was necessary to prove that a
computer was operating properly and was not used improperly
before any statement in a document produced by the computer could
be admitted in evidence. The position since 2000 has been a
common law rebuttable presumption that a computer was operating
correctly at the material time, unless there is explicit evidence
to the contrary.
- There has been a call for changes to this presumption from a
number of those with expertise in both software and the criminal
law, and the recent Horizon scandal, amongst other cases, has
highlighted the urgent need to review this position.
- Since the repeal of s.69 of the scope and scale of ‘computer
evidence' in criminal prosecutions has proliferated, in ways
which may not have been fully foreseen at the time. It is
important that we consider what legislative changes might be
needed to the way in which this type of evidence is dealt with in
prosecutions. However, any proposed changes must be well thought
through and informed by a wide range of expertise and best
available evidence to mitigate against any unforeseen
consequences which could delay or derail the prosecution of
suspected offenders, or indeed lead to further miscarriages of
justice.
