MIL-OSI United Kingdom: Initial findings of our e-discovery review

We use software to help identify evidence and other relevant material for use in our criminal investigations and prosecutions.

This ensures we can process very large amounts of digital material across our cases and is line with the approach taken by most law enforcement agencies.   

At present, the SFO is reviewing our current and past use of this software.  

A sufficiently large amount of work has been undertaken as part of this review so that I can now provide a substantive update. Some of this work is ongoing. 

Our current system  

The SFO currently uses the software OpenText Axcelerate (“Axcelerate”). 

As with many software programs, it is usual to find and patch software issues from time to time.  

Recently, we finished applying a technical fix to Axcelerate after our staff identified an “encoding issue” affecting the way some words appeared in documents ingested into the system.    

This work took some months but is now complete and the issue has been corrected.  

We have already informed all relevant defendants about this fix across our cases in court and will continue to share information with future defendants in the normal way via pre-trial proceedings.   

We remain confident in the efficacy and integrity of our system.  

Our past system  

With input from the Attorney General’s Office and His Majesty’s Crown Prosecution Service Inspectorate (“HMCPSI”), the SFO has also commenced a review of our past use of software called Autonomy Introspect (“Autonomy”). 

The issue we have identified with this software is different. The version of Autonomy used by the SFO in the past had some specific rules that governed the way search terms had to be constructed to identify variations of the word being searched.  

The way Autonomy’s search function worked was explained in two cases at court, and we have also discussed it with the independent body that reviews our work, HMCPSI.    

The SFO, like all prosecutors, has a legal obligation to disclose material to any convicted defendant which might cast doubt upon the safety of that person’s conviction and to undertake enquiries to ascertain whether such material exists.   

We take this obligation very seriously and we recognise that, although we have not seen any evidence of this yet, this issue with search terms could have resulted in relevant and disclosable material being missed.  

Therefore, we have decided to look back at our Autonomy cases to see how search terms were constructed and used by our case teams in the past. This work is well underway and we have now completed an initial review of every relevant case, prioritising cases where defendants are serving custodial sentences.  

As a result, we have identified many cases which were clearly not affected by the issue. However, in some cases, further enquiries are needed and so we have not yet reached a decision as to whether those cases were affected or not. This work is ongoing and will likely involve some searches being re-run on some cases. 

In all cases we have reviewed to date, we have not seen any material which undermines the safety of any conviction. 

A dedicated senior working group at the SFO, led by Interim Director of Legal Services Matthew Wagstaff, is coordinating this review with independent input from the Attorney General’s Office and HMCPSI.  

The work of the senior working group is also being overseen by an independent oversight group. 

We are contacting defendants and their legal teams, where we have address details for them, to update them on this process, setting out in detail the action we have taken.   

If you think this should include you – and you or your lawyer have not already been contacted by us – you can reach us at public.enquiries@sfo.gov.uk.  

We are committed to continuing to publish relevant information and we expect to provide a further update in the coming months.   

Q&A  (For reactive use with media/stakeholders and to support SFO leads internally)

What software is involved in these reviews? 

There are two types of software involved in these reviews. The first is Autonomy Introspect, which is no longer used by the SFO. The second is OpenText Axcelerate which remains our current e-discovery software.  

What are the issues with the software?  

A feature of the SFO’s version of Autonomy Introspect was that when search terms were run certain punctuation marks were treated as “tangible” characters as opposed to “non-tangible” characters. The characters in question were:  

• % – Percentage symbol 

• @ – At symbol 

• / – Forward slash 

• : – Colon  

• . – Full stop 

• £ – Pound sign 

Tangible characters are ones which a search function looks for, whilst non-tangible are ones which are ignored. The result as far as Autonomy was concerned is that where one of the tangible characters appeared adjacent to a word which was being searched for it would be treated as two completely different words. For example, a search for “bribe” would not return an instance when it is directly followed by a full stop (e.g. “bribe.”).  

Our guidance and training took this into account when setting out how to operate the software. But it emerged that search terms used on cases did not always account for this feature.  

With Axcelerate, a case team identified that an “encoding” setting meant a limited number of searches were potentially ineffective. This was because additional characters were added when text was copied which subsequently affected searches.  

What action have you taken?  

We are reviewing how search terms were used historically on Autonomy Introspect by teams. Where necessary we will be re-running search terms and dip-sampling the results to check whether any material was missed which might now cast doubt on the safety of the conviction. 

In the case of Axcelerate, teams have re-run searches, informed defence teams as appropriate and developed and tested a permanent fix for all searches. This has been successfully implemented.  

When were these concerns identified?  

We became aware in September 2022 on the G4S case that searches undertaken with Autonomy Introspect needed to be re-run with revised search terms.  

HMCPSI, the independent inspectorate, was aware of the issue during its recent inspection of disclosure at the SFO.  

In February 2024, the team investigating the London Mining case identified the “encoding” concern with Axcelerate  

What happens next? 

We will be contacting those parties affected and their legal teams to share details of the reviews which have been undertaken.  

We will publish further updates on the progress of this work when appropriate.  

Will you make public the number of cases the Autonomy issue affects?   

We will publish only accurate information, that we have verified is correct. The number of cases we are looking at has changed as we have conducted our review and determined which cases are within scope, and it may change again. We may publish our final figures once this work is complete.   

How many Axcelerate cases does this affect?  

The Axcelerate issue has been resolved. We will not provide this figure, as this would reveal the SFO’s covert caseload.