Who can administer an oath or affirmation?

If an oath or affirmation is required for a document or procedure the following are able to administer it in relation to an affidavit:

Commissioner for Oaths

Circuit Judges and District Judges (section 58 County Courts Act 1984)

Justices of the Peace (section 58 County Courts Act 1984)

certain officials of the Supreme Court (section 2 Commissioner for Oaths Act 1889)

certain officials of the County Court appointed by the presiding judge of that court (section 2 Commissioner for Oaths Act 1889)

Official Receivers and Deputy Official Receivers (Insovency Rules 1986 rule 7.57(4)) 

It is very important that affidavits are not sworn by someone who is in any way involved in proceedings that it relates to.

Alterations

If an affidavit is altered it must be initialled by the deponent and and by the person who administered the oath. Otherwise it can only be used as evidence if the court grants permission to do so.