The Politics Show has learned that the Scottish Government has been looking at how much revenue it would raise if it extended its plans for a local income tax to cover investments as well as earned income.
The SNP's consultation process on their plans for a local income tax closed in July 2008.
The proposals included a 3% rate on earned income.
But "savings and investment income" was explicitly exempted.
However, using the Freedom of Information laws, the we have uncovered e-mails sent from the Scottish Executive to Her Majesty's Revenue and Customs in September.
On the 23 September 2008, an official working at for the Scottish Executive wrote to HMRC:
"You may remember that I got in touch with you over a year ago requesting information on... how much revenue we could raise from the Local Income Tax...
...we are now trying to assess how much money could be raised from investment income if a LIT was applied to this".
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