House of Commons

Letter from Professor Dame Carol Propper to Seamus Logan MP – statements on water quality

Dear Mr Logan,

Thank you for your email of 5 September to the Acting National Statistician regarding comments by the former Secretary of State for Environment, Food and Rural Affairs, that drew comparisons between England and Scotland’s water industry regulation.

I respond on behalf of the UK Statistics Authority’s Regulation Committee, which oversees the independent regulator, the Office for Statistics Regulation (OSR). Whereas normally the Chair of the Authority would respond to your concern, she has instead asked me to respond in her place, to avoid the risk of a perceived conflict of interest with another role.

Judgements about regulation of the water industry and broader environmental policy are rightly for you and your colleagues in the UK Parliament and devolved assemblies to consider. However, we have looked at some of the statements made as part of our role enforcing the Code of Practice for Statistics; a full list of these is enclosed in Annex A.

In brief, we consider that these statements lacked enough transparency about their sources to be verified, and that the broad evidence did not support them. Without appropriate discussion of the limitations of some of the more specific figures quoted, they run the risk of misleading the public.

As you point out, the then-Secretary of State said several times that water pollution and water quality are worse in Scotland than in England. He made these claims repeatedly in the House of Commons, as well as in broadcast interviews and online. We also note his letter of 24 July to Stephen Flynn MP published on X, which cites a range of statistics in response to the dispute over his claims.

The table of figures appended to the letter is not relevant to water pollution and water quality, but in the body of his letter he further claimed, without providing a source, that in 2023-24, there were 35.8 pollution incidents per 10,000km of sewerage network in Scotland, and 35.4 in England and Wales combined.

The Department for Environment, Food and Rural Affairs told us that its source for Scotland was an analysis of Scottish Water’s annual report, and for England and Wales, Ofwat’s water company performance report, wherein pollution incident rates are broken down by company. The sector average given for both England and Wales combined is 35.42. These water companies’ territories do not neatly match national boundaries, so it is not simple to calculate pollution incidents in England alone.

Underlying regulatory data on pollution incidents are not yet available for Wales or Scotland, although an Environmental Standards Scotland report claims Scottish Water has a lower incident rate (36) than English water companies (41), when including incidents from water supply assets. However, there are many differences in monitoring and reporting of pollution incidents data, so the Independent Water Commission (IWC) cautions against making these comparisons between countries. It is important to provide this context when referring to them in public debate.

The IWC concluded its review of the water sector on 21 July, and in its final report there are several sets of statistics directly relevant to water quality and other environmental data. It would have greatly improved public understanding to draw upon these figures, given their relevance, quality, and importance to the Government’s stated ambitions. The figures show broadly that Scotland has a similar or better share of bathing and surface water sites that meet good or excellent standards for water quality. The OSR has published a further analysis of this topic, which I enclose in Annex B.

The Authority expects that ministers take care to avoid using data that is overly selective or missing appropriate context. Based on the statements made without discussion of their context, sources, and limitations, there is the potential for people to be misled about English and Scottish water quality and infrastructure. As former Chairs have said, omitting this kind of information can damage public trust in the data, so we encourage those speaking on behalf of Government to ensure statistical statements are presented clearly and transparently, in a way that supports public understanding.

Yours sincerely,

Professor Dame Carol Propper
Chair of the Regulation Committee

Annex A

“[…] you were just hearing about Scottish Water, they’re nationalised, pollution in rivers in Scotland is worse than in England”
Sunday with Laura Kuenssberg, BBC One, 20 July
“In Scotland they have a nationalised water company, but pollution levels in Scotland are worse than they are in England“
Channel 4 News, 21 July
“Scotland has a nationalised water company… and water pollution is worse than in England as a result”
House of Commons, 21 July and republished online at X.com
“… under the nationalised model in Scotland, pollution is worse, not better.”
House of Commons, 21 July
“Official statistics […] show several areas where Scotland’s water quality underperforms relative to England.”
Letter to Stephen Flynn MP, 24 July
“There were 35.8 incidents per 10,000km of sewer in Scotland versus 35.4 incidents per 10,000km of sewer in England and Wales reported in 2023-24.”
Letter to Stephen Flynn MP, 24 July
“OFFICIAL: The SNP are managing water pollution in Scotland even worse than the Tories did in England”
@SteveReedMP on X.com, 25 July
“Levels of pollution in England are bad enough, but under the SNP in Scotland they are even worse”
House of Commons, 4 September
“I have published the data and I stand by it: pollution under the SNP in Scotland is even worse than it was under the Tories in England.”
House of Commons, 4 September

Annex B

OSR statement on statistics concerning aspects of water in Scotland and England

Seamus Logan MP to Emma Rourke – statements on water quality

Dear Emma,

Recent Usage of ONS Data by The Rt Hon Steve Reed MP

I hope this email finds you well.

I am contacting you in relation to recent comments made by the Secretary of State for Environment, Food and Rural Affairs and his usage of ONS data.

The Minister has cited the attached statistics regarding water monitoring in Scotland to argue that pollution in Scotland is worse than in England and that nationalised water systems in general perform worse than privatised systems.

The Minister’s initial comments in the Chamber can be found here.

I also link to comments made in the chamber by the Secretary of State citing these figures (published on social media here), which he claimed yesterday he “stood by”.

This seems to be at odds with other statistical analysis done by SEPA and the Independent Water Commission. SEPA reported that 87% of Scotland’s entire water environment as having a ‘high’ or ‘good’ classification for water quality – up from 82% in 2014. The Independent Water Commission found that 66% of Scotland’s water bodies are of good ecological status as compared with 16.1% in England and 29.9% in Wales.

I should be grateful if you would provide me with a view of your interpretation of these ONS statistics and whether you consider the Minister’s conclusion as a reasonable interpretation in light of the wider context and statistics.

With best wishes.

Yours sincerely

Seamus Logan MP
Member of Parliament for Aberdeenshire North & Moray East

Letter from Sir Robert Chote to Helen Morgan MP – NHS appointment statistics

Dear Ms Morgan,

Thank you for your letter regarding the Government’s claim of delivering 3.6 million additional NHS appointments in the first eight months of its term.

The OSR has verified the accuracy of the figure of 3.6 million additional elective appointments based on official statistics produced by NHS England, compared to the same period in the previous year.

On the question as to whether this represents a ‘massive increase’ in NHS activity, this is outside of our remit to comment on. We do not seek to be a mediator in political debate; however it is important that information is available that allows informed public debate. At the time the press releases you referred to were published, it was not possible to consider the scale of the increase in a historical context as the data were not available prior to July 2023. Given the importance of this matter, the OSR has engaged with NHS England and we are pleased to report that the data back to April 2018 have now been published.

You raised a concern that the Government had not defined how it was measuring appointments or what baseline it was using. The OSR reviewed the Labour Party Manifesto, the Government’s ‘Plan for Change’ and press releases, and determined that the measure of their target for extra appointments, which is defined in the official statistics as ‘additional elective operations, appointments and tests’, has generally been communicated clearly and consistently. In addition, the Government has been transparent that the target was to be measured against the previous year’s figures.

Thank you again for bringing this matter to our attention.

Yours sincerely,

Sir Robert Chote
Chair

Letter from Sir Robert Chote to James Cartlidge MP – Chagos Islands deal

Dear Mr Cartlidge,

Thank you for your letter expressing concerns around the presentation of the cost of the Chagos Islands deal outlined by the Prime Minister in a press statement on 22 May. Specifically, he stated that

“£101 million a year is the average cost; the net overall cost is therefore £3.4 billion overall, that’s over the 99 years”.

You raised two concerns; first, that the Social Time Preference Rate used to calculate the figure of £3.4 billion was not the most appropriate measure, and second, that the source for the £3.4 billion had not been made available.

It is beyond the remit of the Office for Statistics Regulation (OSR) to determine the most appropriate discount rate to use for such calculations. But given the Government’s reference to the Office for Budget Responsibility (OBR) in defence of its chosen figure, we have confirmed with the OBR that they believe that this is a reasonable one to use when discounting the value of a lease.

The OSR has considered the transparency with which the calculation was communicated within the press statement. The press release provides a range of information for readers, including Notes for Editors. Our one concern is that by describing the £3.4 billion figure as the net overall cost, it was not made clear to the public that the figure was calculated using a discounting method.

In relation to the source of the calculation, the explanatory memorandum explains how the £3.4 billion figure was calculated, including reference to the use of the Social Time Preference Rate for discounting. We welcome that this information was made public at the time of the press statement in line with the principles of intelligent transparency. In future, we would encourage a link to this explanatory memorandum to be provided within the press statement in order to better support the public in understanding and scrutinising the figure.

We have raised these two points with the Prime Minister’s office and the Foreign, Commonwealth & Development Office.

Thank you again for raising this issue.

Yours sincerely,

Sir Robert Chote
Chair

Helen Morgan MP to Sir Robert Chote – NHS appointment statistics

Dear Sir Robert,

I am writing to raise concerns about the possible misrepresentation of official NHS statistics by the Government in relation to its pledge to deliver two million extra appointments.

In February 2025, Health Secretary Wes Streeting announced that the Government had not only met its pledge early but had achieved a “massive increase” in NHS activity, citing 3.6 million additional appointments in their first eight months. This figure has since been widely used by ministers and Labour MPs as evidence of substantial progress.

Data obtained through a Freedom of Information request by the independent fact-checking charity Full Fact, however, shows the opposite: new NHS activity has slowed under this government.

The Nuffield Trust have described the two million target as “very modest”, while the Institute for Fiscal Studies said it was smaller than the annual growth in demand pressures forecast by the Government. In fact, it represents less than a 3% increase in activity. These facts directly contradict the narrative of an impressive ramping up of activity.

Additionally, the Government failed for months to define how it was measuring appointments or what baseline it was using, hindering independent verification. Only after the announcement that the pledge had been met did ministers release a partial definition, still without the baseline figures needed to properly assess performance.

The presentation of this data as a substantial acceleration in NHS delivery, without context or full transparency, appears to mislead the public about the true state of progress. I therefore ask that you investigate the Government’s statements regarding NHS appointment statistics, and offer your guidance on whether they accurately reflect the underlying data and trends.

I look forward to your response.

Yours sincerely,
Helen Morgan MP, Liberal Democrat Spokesperson for Health and Care

James Cartlidge MP to Sir Robert Chote – Chagos Islands deal

Dear Sir Robert,

Misuse of statistics by the Prime Minister regarding the Chagos Islands surrender deal

I am writing to ask you to investigate claims made by the Prime Minister about the cost of the deal to surrender sovereignty of the Chagos Islands to Mauritius.

Yesterday, when asked about the cost of the deal, the Prime Minister claimed it would be £3.4 billion, even after accounting for inflation. This figure is inaccurate.^[1]

Independent analysis suggests that, once a conservative rate of inflation is accounted for, the true cost of the deal is likely to be in excess £30 billion. That’s a difference of £27 billion – a substantial amount that could mislead the public about the real financial cost.^[2]

I understand the government has used the Social Time Preference Rate (STPR) to calculate the figure used by the Prime Minister. The figure is therefore a representation of ‘social time preference’, not a representation of the direct cost to the taxpayer. However, the Prime Minister stated that:^[3]

‘That is the net cost, and the reason it is put in those terms is because it is how the Government accounts for it, it is how the OBR counts the cost, and it is the way public sector projects are measured. In other words, what’s the net cost is today? And that is £3.4 billion. Obviously over time, with inflation, then that is the net cost’^[4]

The Prime Minister has therefore misrepresented the figure by stating that it is a net cost when in reality it is a figure for the social time preference. Such discounting in the public sector is intended to allow the costs and benefits of different policies with varying time spans to be compared on a common basis. But in this case, it is being used as a statistical sleight of hand to hide the true cost to taxpayers of this surrender deal and appears to be a breach in the Code of Practice on Statistics which states that:

‘Statistics, data and explanatory material should be presented impartially and objectively’^[5]

Furthermore, the government has failed to publish the source statistics despite the Code of Practice on Statistics stating:

‘Policy, press or ministerial statements referring to regular or ad hoc official statistics should be issued separately from, and contain a prominent link to, the source statistics’^[6]

The government’s failure to publish the statistical methodology therefore appears to be in breach of the Code of Practice on Statistics.

As the UK Statistics Authority, your role is to promote transparency and accuracy in the use of public data. I therefore ask you to investigate whether the Prime Minister’s figure follows the Code of Practice on Statistics to make sure that public confidence in public statistics is upheld.

The public deserves clarity on this matter, especially given the government’s cuts to the Winter Fuel Payment and the tax hikes it has imposed on businesses. A transparent assessment will help to maintain trust in official figures.

I am placing this letter in the public domain.

Yours sincerely,

James Cartlidge MP
Shadow Secretary of State for Defence

Footnotes

^[1] In response to a question from David Shephard from the Financial Times yesterday, the Prime Minister said: ‘That is the net cost, and the reason it is put in those terms is because it is how the Government accounts for it, it is how the OBR counts the cost, and it is the way public sector projects are measured. In other words, what’s the net cost is today? And that is £3.4 billion’ (Prime Minister and Defence Secretary Statement on Chagos Islands, 22 May 2025, archived).
^[2] The Daily Telegraph, 22 May 2025, archived.
^[3] GOV.UK, UK/Mauritius, 22 May 2025, link.
^[4] Prime Minister and Defence Secretary Statement on Chagos Islands, 22 May 2025, archived.
^[5] ONS, Code of Practice for Statistics, 5 May 2022, link.
^[6] ONS, Code of Practice for Statistics, 5 May 2022, link.

Letter from Sir Robert Chote to Matt Vickers MP – police workforce figures

Dear Mr Vickers,

Thank you for your letter of 21 February regarding the use of police workforce statistics by Dame Diana Johnson, Minister of State for Police, Crime and Fire.

The claim in question was made during the debate on the Police Grant Report on 5 February 2025. The Minister stated,

“there were 149,769 police officers in March 2024, but in June – when the Conservative Government were still in power – that figure had been reduced by 1,232 to 148,536 officers.”

We examined this and determined that the figures cited by the Minister were published on 22 January 2025 as an annex in the Police workforce: 30 September 2024 bulletin. As such, the figures were publicly available at the time the claim was made.

However, we note that these figures are published management information rather than part of the regular statistics on police numbers, and so were not included or referred to in the separate data tables accompanying the bulletin.

We have discussed this approach with Home Office statisticians and will continue to support them in finding the best ways to publish management information outside of regular statistical releases, so that they are readily accessible when ministers and officials use them publicly. Thank you again for raising this matter with us.

Yours sincerely,

Sir Robert Chote
Chair

Matt Vickers MP to Sir Robert Chote – police workforce figures

Dear Mr Chote,

I am writing to formally complain about the use of unpublished statistics by the Minister of State for Police, Crime and Fire during a statement made in the House of Commons chamber when closing the debate on the Police Funding Settlement on 5^th February 2025.

During the statement, the Minister cited a police workforce figure “had been reduced by 1,232 to 148,536 officers” in June, despite the official publication schedule dictating that police workforce statistics are only released in March and September. As I understand it, the release of this figure is a clear breach of established statistical protocols and raises concerns about the proper and transparent use of official statistics.

The UK Statistics Authority’s Code of Practice for Statistics emphasises the importance of orderly release and preventing the misuse of statistics. The Minister’s announcement appears to contravene these principles by disclosing unpublished figures without making them publicly available in a consistent and transparent manner. As I understand it, no previous publications of police headcount numbers were announced in the month of June in previous years – making it impossible for trends or changes to be compared.

I request that the UK Statistics Authority investigates this matter and provides clarification on whether the Minister’s actions were in line with the Code of Practice. Additionally, I would appreciate a response outlining any steps the Authority may take to ensure ministers adhere to proper statistical procedures in the future.

Thank you for your attention to this matter. I look forward to your response.

Yours sincerely,

Matt Vickers
Member of Parliament for Stockton West
Shadow Minister of State for Police, Crime and Fire

Letter from Sir Robert Chote to Kieran Mullan MP – statistics on criminal records

Dear Dr Mullan,

Thank you for your letter regarding statements by Lord Timpson OBE, Minister of State for Prisons, Probation and Reducing Reoffending, on the proportion of the population with a criminal record.

The first statement was made by Lord Timpson in the House of Lords on 24 July 2024 and stated that:

“The criminal justice system exists to keep the public safe, but it should not hold back the one in four working-age people in the UK with a criminal record from getting jobs.”

This claim is based on information provided in an ad-hoc release by the Ministry of Justice in October estimating the number of individuals with a nominal record on the Police National Computer. As summarised within the release, there are a number of limitations for these data and the figure of ‘one in four’ should only be used as a high-level estimate.

Your additional concerns related to claims made in an article published by The Times on 9 January 2025. Within the article, the terms ‘criminal record’ and ‘criminal conviction’ are used seemingly interchangeably, which is imprecise – a criminal record is not the same as a criminal conviction – and the claims referring to criminal convictions are therefore not supported by the Ministry of Justice release. Furthermore, the article is also not always clear that the proportion of individuals with a criminal record relates specifically to the working age population (those aged 16-64) and not the whole population.

It is important that when using figures publicly, they are quoted accurately to best support public understanding on these issues. We have raised this matter with Lord Timpson’s office.

Yours sincerely,

Sir Robert Chote
Chair

Letter from Sir Robert Chote to Nick Timothy MP – costs associated with Illegal Migration Act

Dear Mr Timothy,

Thank you for your letter regarding statements made by the Home Secretary on 22 July about a change to the Illegal Migration Act (which would enable the Government to legally begin processing some asylum cases in the UK, rather than being obliged to remove those applicants from the UK first).

Specifically, you raised concerns that some of the estimated savings of £7 billion from this change was calculated by “double counting”: adding the costs of removing some applicants to the estimated costs of instead accommodating them in the UK.

On 22 July the Home Secretary told Parliament:

“Two and a half years after the previous Government launched it, I can report that [the Rwanda Migration and Economic Development Partnership] has already cost the British taxpayer £700 million… Making this one simple change will save the taxpayer an estimated £7 billion over the next 10 years.”

In response to your questions about this part of her statement, the Permanent Secretary of the Home Office wrote to you on 16 August. His letter said that “the Home Secretary’s statement included” the figure of £700 million of costs related to UK-Rwanda Partnership. He then wrote that “further detail is contained” within the Impact Assessment of the change to the law, from which the £7 billion of future savings was calculated. This indicated that the figures of £700 million and £7 billion were related.

Having discussed this issue with the Home Office, we established that the £700 million of costs are not included in the estimated £7 billion of savings outlined in the Impact Assessment and that they cover different time periods. The Permanent Secretary’s letter was not clear about the difference between these two figures, but since then the department has released a further breakdown of the £700 million which makes this more obvious.

It is important that Government correspondence is clear and transparent on issues of great public interest, referring precisely to published data. This enables Parliament and the public to understand and independently scrutinise government decision-making.

Yours sincerely,

Sir Robert Chote
Chair

Letter from Professor Dame Carol Propper to Seamus Logan MP – statements on water quality

Annex A

Annex B

Related links

Seamus Logan MP to Emma Rourke – statements on water quality

Recent Usage of ONS Data by The Rt Hon Steve Reed MP

Related links

Letter from Sir Robert Chote to Helen Morgan MP – NHS appointment statistics

Related links

Letter from Sir Robert Chote to James Cartlidge MP – Chagos Islands deal

Related links

Helen Morgan MP to Sir Robert Chote – NHS appointment statistics

Related links

James Cartlidge MP to Sir Robert Chote – Chagos Islands deal

Misuse of statistics by the Prime Minister regarding the Chagos Islands surrender deal

Footnotes

Related links

Letter from Sir Robert Chote to Matt Vickers MP – police workforce figures

Related links

Matt Vickers MP to Sir Robert Chote – police workforce figures

Related links

Letter from Sir Robert Chote to Kieran Mullan MP – statistics on criminal records

Related links

Letter from Sir Robert Chote to Nick Timothy MP – costs associated with Illegal Migration Act

Related links