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HMRC internal manual

Technical Teams Operational Guidance

Investigation work: Code of practice 9: protective assessments

There can be some difficult choices to be made on raising assessments to encourage the submission of a report. Where a report is delayed it will often be preferable to take over the investigation yourself. See TTOG4415.

Investigators should consider each case on its merits, and take note of the advice at TTOG4425 and onwards. In particular, consider what your next step will be when the taxpayer appeals and applies for postponement of the tax. If you are not ready to contest these actions, your assessments will not have taken you any further forward.