Each referee must have known you personally for at least 3 years. One referee should be a person of professional standing, such as a doctor, a minister of religion, civil servant or a member of a professional body eg accountant or solicitor (but not representing you with this application). The other must be the holder of a current British citizen passport. Each should be:
We will not accept a referee who has been convicted of an imprisonable offence during the last 10 years and the sentence has not become spent under the Rehabilitation of Offenders Act 1974...
We will not accept a referee who is or appears to be your relative.
Checks will be carried out to ensure that the referees do not have unspent convictions ... and that the referee holding a British passport is qualified to act for you and that their signature is genuine. It is a criminal offence to provide false information knowingly or recklessly punishable with up to 3 months imprisonment or by a fine not exceeding £5,000 or both under section 46(1) of the British Nationality Act 1981.
The JCWI Manual informs us that one referee must be British and that both referees may be British citizens.
One of the referees must be a "professional". From the Nationality Advice Line, we have the following list of acceptable professions (NOTE: this is a partial list current as of April 2007).
What happens if I have a referee who is not on this list?
The list of acceptable professions is purely indicative and not meant to be exhaustive. New professions are added on an 'as needed' basis. We have never seen a refusal where the applicant's professional referee was diligently selected.
Reviewed and updated 5 May 2012