Millions of dollars has been raised from anonymous US donors to support British rightwing thinktanks that are among the most prominent in the Brexit debate.
American donors are giving money to US fundraising bodies that pass the donations to four thinktanks in Britain. A Guardian analysis has established that $5.6m (£4.3m) has been donated to these US entities since 2008.
The Institute of Economic Affairs (IEA), the Adam Smith Institute, Policy Exchange and the Legatum Institute have all received financial support from US backers via this route.
The disclosure leaves the thinktanks facing questions as to whether wealthy Americans have undue influence in British politics, particularly over the form Brexit takes.
The UK thinktanks are some of strongest proponents of radical free trade deals with reduced regulation – positions likely to benefit big American businesses, which have opposed Europe’s tighter regulations since the 2008 financial crash.
They have a policy of not disclosing their donors, arguing they respect their backers’ right to privacy unless the backers wish otherwise. Critics say the lack of transparency allows unseen donors to influence political debate.
The charitable status of the thinktanks requires them to remain non-partisan, and they all insist they have not taken a line as institutions on whether the UK should leave the EU.
However, they have published or contributed to policy papers that advocate a Brexit deal that makes a clean break from European regulations.
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