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HMRC internal manual

Fraud Civil Investigation Manual

Where CDF offer is made 30 June 2014 onwards: opening the investigation: do not disclose your concerns

The Contractual Disclosure Facility (CDF) procedure allows the customer the opportunity to make a full disclosure at the start of your investigation. This means that you must not disclose details of your evidence or concerns at the outset, see FCIM203050.

You no longer need to indicate at the outset the tax regime or regimes under which your concerns lie.