Sir Winston Churchill and the 1960s Ultra Security Breach

 

In 1960 the Joint Intelligence Committee found itself with an unexpected problem. Among the challenges of the Cold War and attempting to predict what the Soviet Union may attempt next, it was also identified that the content of some of Sir Winston Churchills papers, then under transfer to the  Archives  was potentially about to cause a major diplomatic incident with the USA. This led to urgent ‘action this day’ to resolve the matter. This is the previously untold story of the Churchill papers.

Like many leaders, Churchill accrued a significant amount of files governing his personal life, as well as records of his time in public office. To this day they remain accessible via the ‘Churchill Archives’ which stores thousands of papers linked to his time in public office including as Prime Minister during the 2^nd World War (known as the ‘Chartwell Papers’) and also the later period of his life after July 1945 (known as the ‘Churchill Papers’).  The Chartwell Papers contain files relating from 1884 until 1945, covering practically every aspect of his personal and professional life from speeches to personal correspondence to family and friends.

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After Churchill left office in 1945, the records relating to his time in Government were held by three different organisations. This included the Chartwell Trust, the Cabinet Office and No10 Downing Street. These records were mostly innocuous, and while fascinating on one level, giving an insight into his life and thinking, there was little controversial about them. The challenge though came in 1960 when it became clear that there was more to the archives content than had perhaps been realised…

The story of the breaking of the Enigma code remains one of the most incredible stories of allied cooperation and success in WW2. It was also for many decades one of the most closely guarded secrets of the war. The fact that the allies had been able to read Axis message traffic and use it to their advantage remained incredibly sensitive for years afterwards – in part because the methods and techniques used continued to form the basis of post war SIGINT collection by GCHQ and the NSA.

The problem was that public records in the UK can usually be released to the National Archives (then known as the Public Records Office) after 30-50 years. In the 1950s and 1960s there was growing concern that this could potentially jeopardise the Enigma secret. In a letter to the JIC from GCHQ dated July 1960 on the subject of the security of WW2 SIGINT , it was noted that: “We have been concerned for some time with the effect for the regulations of placing documents in the Public Records Office on the security of files which contain information derived from SIGINT in WW2 and which by virtue of the passage of time would be candidates for lodging in the PRO”.

It was explained that, in 1948 the UK Joint Intelligence Committee agreed guidelines to issue to official historians on how to manage the challenges of writing history documents relating to WW2 and protecting the enigma secret. In an official paper – JIC(48) 14(0), the JIC advised that:

“Although the war has ended, it is still a vital necessity that no hint concerning the extent or value of this information be given. The two main reasons for this are:

a)      Other enemies may arise in the future. Were they to know what successes were achieved as a result of this special source, they would ensure that this source is not available to us. 

b)     No possible excuse must be given to the Germans or Japanese to explain away their complete defeat by force of arms. Knowing that this source of information was available to us would provide such an excuse”.

This points to the concerns held by the British about the importance of protecting Enigma, even long after the war was over. It also points too to the concerns even years after the war ended about changing the narrative of defeat to one of ‘cheating’. It is hard to remember now, but this was written barely 3 years after WW2, and 30 years after WW1 ended. It was clear that attitudes towards former foes had barely begun to soften. In 1956 the JIC again reviewed the subject of what to do with Enigma and wider SIGINT related material and agreed further guidance to historians that: “No document giving information of secret intelligence techniques or sources, or containing any material which would reveal such techniques or sources should ever be made available to the PRO”. It went on to confirm that even in 1960 there was no intention to declassify Enigma papers and that it was vital that they be stored appropriately to prevent their release to the PRO.

Churchills papers were seen as a key source of material that could contain Enigma derived material, and where extra care was needed to protect them from release – for example ‘indoctrinating’ (reading in) historians to the enigma secret to make sure they understood the importance of protecting it, and minimising who could see it. Of itself it is incredible to think that 15 years after WW2 ended, people were still required to be read into Enigma and its mysteries. The challenge was that already a leak had occurred that had caused a minor diplomatic incident...

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In 1958 the Cabinet Office was caught up in an embarrassing breach, when GCHQ had to notify them that a Cabinet Office historian had sent their opposite number in the USA a copy of Churchills papers which contained Enigma (then referred to as COMINT) material without knowing the provenance of the paper and led to the publication of Codeword material in the USA. This was identified as a major breach of the bilateral BRUSA act, which governed the UK / US intelligence sharing relationship, and required GCHQ to take urgent action to resolve the problem.

Accordingly, the Cabinet Office historians suddenly found themselves being indoctrinated into Enigma, to understand the importance of what they were looking at, and why it was so critical to protect it.  GCHQ then conducted a sampling exercise of some of the 516 papers held by the Cabinet Office, selecting 9 at random to see what they contained. Unfortunately, the results were awkward – As a letter from GCHQ to the Cabinet Office put it “the finding of 3 wartime COMINT codeword papers in 9 out of the 516 Churchill files has caused some disquiet at GCHQ” To resolve this, GCHQ requested that they be able to review all the remaining files, trying to identify paperwork that may contain Enigma related material. In turn this would be passed into the custody of the JIC for safe keeping and study by ‘suitably indoctrinated persons’.

The JIC though had concerns about the handling of the process and how to protect the long-term national interest. Their concern was that these files when identified would still need to be weeded to determine if they were of interest to the PRO, and if so, how to protect them. While it was possible to protect the documents from release via a ‘Lord Chancellors Instrument’ which would prevent their release for a while, this would not hold indefinitely, and GCHQ would need to accept that at some point the files would become public.

What is interesting at this stage is that in 1960, the view of the Cabinet Office was that it would take at least 50 years for files to be handed over to the PRO. As they noted in their letter “under this procedure WW2 records will not be passed to the PRO until 1989 at the earliest”. It went on to suggest that to help ensure the files were properly recorded and understood, that GCHQ should undertake to provide a copy of all WW2 related SIGINT codewords to help future analysis of files for relevance as “I suggest this would be better done now before memories fade, as I am sure that this will be helpful to our successors who will have to grapple with this problem in the 1980s, assuming of course that SIGINT cannot be downgraded after 50 years’!

The JIC went on to note slightly tongue in cheek that due to the 50-year rule, their head historian (Mr Woods) was concerned with handing over ‘records of 1910 vintage’ and “unless GCHQ therefore has any reservation about what can be revealed about SIGINT operations in World War 1, we can safely relax for the time being. Perhaps you can tell me of any precautions that should be observed in dealing with WW1 papers”

The GCHQ response was to delicately note that “it seems that the activities and successes of our predecessors have been so widely noted that there is little point in making any special reservation regarding the passing of the WW1 files to the PRO”. Again, it feels incredible looking back to realise that WW1 had ended only 42 years previously, and that when the letter was written, the SIGINT operations of that war were still seen as sensitive.

The GCHQ weeding was successful with 55 documents being removed from the main files and taken into storage by the JIC. Most of them contained codewords and material relevant to WW2, but it seems that some clearly applied to other more current operations, to which the Enigma indoctrinated historians were not permitted to know. The historian who led the weeding work had to confess in a memo to showing an Enigma historian a folio containing a more current Codeword but “fortunately he will no doubt be put on the current indoctrination list when he joins the JIC secretariat in January, so I have relaxed”!

This should have been where the story ended, but unfortunately, events were to take a turn for the worse. In June 1963 GCHQ sent a letter that began with the delightfully cryptic line “certain regulations are currently in force to safeguard the Special Intelligence Source which was exploited so successfully during the 1939-45 war”.

It went on to state that although the JIC held 55 Enigma related papers in safekeeping, it had been informed by the Cabinet Office that the Chartwell Trust had passed the papers in its keeping to the PRO for cataloguing, photographing and then being passed to Randolph Churchill ahead of his publication of his biography on Sir Winston Churchill. In other words, after all the efforts to safeguard the Enigma secret by GCHQ, it turned out that some of the most sensitive COMINT material in the country, that remained TOP SECRET had been seen and photographed by non-indoctrinated members of what is now, the National Archives. This was not good news to put it mildly…

GCHQ reviewed the files held by the Chartwell Trust and identified that in total some 12 papers containing Enigma material had been seen by the PRO. It also stated that:

“The Chartwell Trust papers also reveal that:

a)      The close association between of the UK Security Service with the Eire Special Branch during the War;

b)      The Drop Copy arrangements for collection of cables from the German embassy in Dublin.

Of a) Churchill wrote to the effect: “I never wish to see this subject again. All copies of this minute is to be destroyed”. The Chartwell Trust copy is still extant”.

This is noteworthy – the author has been unable to find further information either on MI5 & Special Branch cooperation in WW2, or the Drop Copy arrangements, although the latter strongly implies that the UK was reading German embassy traffic with the active support of the Irish State. In both cases this is a remarkable document to uncover. Of separate note is that GCHQ may have made a mistake - another letter suggests that in fact these files covering "the Irish arrangement" were not included.

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The result of these finding was that the Cabinet Secretary (Sir Burke Trend) was informed, and the decision taken to contact the Chartwell Trust and have a difficult conversation. The outcome of this was to provide the Trust with a list of papers that “contained sensitive information of continuing intelligence value” and recommended that all of them be held in the custody of the Cabinet Office (e.g. passed into the same JIC storage file).

The biggest issue for debate though was how to remove the files in the lowest keyway possible. The worry was that if the files were too blatantly removed people would notice the gaps in the sequential filing. It was proposed instead to put a small note, as unobtrusively as possible in the filing structure, to the effect of saying “Because of the continuing intelligence value of the information contained in FO/XXX this document has been removed on the authority of the Trustees of the Chartwell Trust is held in the the Cabinet Office.”

Given the importance of the situation, the Cabinet Secretary personally met the Trusts solicitors to explain the situation in 1963 and got their approval to have the papers removed. The only two stipulations the Trust placed were firstly that there be a formal receipt for the paperwork, to show that it was above board, and secondly, in a note to the Cabinet Secretary from the solicitors handling the case noted that Jock Colville, another trustee and former PS to Churchill suggested that “I should ask you whether, in say 20 years time or whenever the information disclosed by the documents is no longer subject to national security, they could be returned to the Trust archives”.

Sir Burke Trend agreed with this request, although as he wrote to those involved in the case “How long it may be before that happens, no one can yet say; I think we can only leave it, for the present, for an indefinite period. But we shall in the ordinary course review the security classification of the papers from time to time; and you  may be sure that we will not overlook the trustees interest”.  Enigma was formally declassified in the 1970s and fully revealed in the 1990s. It remains unclear though whether the Chartwell Trust ever did receive their papers back, or if to this day, in a lonely forgotten safe deep within the JIC, lie yet to be released papers related to Enigma, their stories yet to be uncovered. Either way, the story of the final Churchill Enigma papers is a fascinating journey into the world of post war SIGINT and how even decades after the end of WW2, Enigma was a secret to be kept at any price.