In this excerpt from my book on Britain and the Colonels, you can see how journalist Mario Modiano, talking to British officials well before the referendum, predicted, with uncanny precision, the exact percentage of the people who would vote 'Yes' to the constitutional changes.
The fact that both foreign journalists and the British Embassy could so easily provide a accurate estimate of the result well in advance speaks volumes about the genuineness of the referendum.
The last important event of [1973's] ‘pretty gruelling summer’, as far as the domestic scene of Greece was concerned, was the referendum on the amended Greek constitution.The junta had warned the British that they should not judge the referendum by British standards and members of the international press had expressed the certainty that it would be ‘a farce’. Mario Modiano [...] thought that the decision to abolish the monarchy had been taken a long time ago, told the British that the Colonels would not permit a repeat of the results of the 1968 plebiscite, in order to make them appear genuine: ‘If as seems likely they fudged the figures, they were likely to choose a more plausible percentage (like for example 78%)’ (emphasis added).This was also the opinion of some FCO officials who had realized, as early as in June 1973, that there was ‘little doubt as to the outcome of the referendum, although the government, who were believed to be embarrassed by the very high yes-votes in 1968, might prefer a rather smaller percentage in their favour this time’.The British conceded that it was ‘very easy’ to predict the outcome of the referendum, with the Colonels still controlling the levers of power and not being able to afford to lose.[...] As [British official J F R] Martin admitted shortly before the referendum, ‘few observers doubt that the figure has been decided in advance to within a few per cent’.Polling took place on 29 July to approve the new republican constitution and the appointment of Papadopoulos as president (reserving for him exclusive powers over defence, foreign affairs and internal security) and Angelis as vice-president.
The final results showed that ‘yes’ got the 78.4% of the vote, which was considered ‘a respectable looking percentage’ in London.The British embassy’s own estimate had been 78% (emphasis added).
The British, however, were in no doubt that there had been ‘a good deal of malpractice’, as they were aware that before the referendum the junta had ‘used all its very considerable influence to ensure the desired result’.
They also did not fail to notice that ‘something perhaps ha[d] changed’, as the regime had been taken by surprise by the strength of feeling against it, and that could result in the toughening of its attitude to palliate the hardliners.
The British representative concluded his report on the events by writing that ‘one [could] not have much confidence that Greece [was] yet firmly on the road leading back to anything that Western Europe would recognise as democracy’ [pp. 185-186].