Civil Investigation of Fraud (Code 9): historical record: the opening meeting: who should attend CIF meeting
The taxpayer is entitled to have a solicitor present (but not publicly funded legal advice as he is not being detained nor is the meeting at a police station) or an accountant/tax adviser present. Indeed we would seek to encourage the person likely to prepare any disclosure report to attend, but it is a matter for the taxpayer to decide who they would like to have present.
Subject to that, in principal there should be at least two officers present at the opening meeting. HMRC staff numbers should not normally exceed those from the other side unless by prior agreement (for example to enable an HMRC Accountant to attend).