@AJT there should be some clues in the wording of the letter as to why the Interview, if it says something like "a query has arisen on your claim" then some busy body has made a phone call and that has caused the interview. Or, they could also just be enquiring about your circumstances.
5% of Customer Compliance cases are selected for "process checks" to ensure that the Compliance people have done what they should have, the rest are because they have suspicions of fraudulent claiming or they have received a "Tip Off".
The most common "triggers" for their involvement are if they believe or have been informed of :-
1) Suspicions of Single Claimants who may be living together as a Husband and Wife or as in a Civil Partnership.
2) You have recently separated from a Partner.
3) You have worked previously as self-employed.
4) They think you have worked without declaring it to DWP.
5) You have sanctions on your benefits and these require discussion.
The Idea behind Customer Compliance interview is to discuss the case in regard to the reason for the Referral and obtain accurate information from the "customer". They will also conduct a Full Review of the "Customer’s" circumstances and they will make a point of "Reinforcing Customer Responsibilities." (tell you what you should and shouldn't be doing !).
It is Not a Criminal Investigation and it will Not be Conducted "Under Caution", however the interveiw will be conducted in a "Robust and Challenging Manner", such that the Compliance Officer does not have to accept initial answers as being the truth. At the end of the Interview they will take a signed Statement from you, either that you write or that they write and you sign (or, if you refuse, that they write and they sign).
You are entitled to have someone with you at the Interview and you can request to record the Interview and they MUST accept your request.
**** I would advise that you ensure you do both of these things !!! ****
If the Interview is because of an Allegation or Tip Off and the Compliance Officer decides it is a Malicious Allegation they can abandon the investigation there and then, although they usually refer all the details of the Interview to a "Decision Maker".
There are some evil people out there who assume because you are on benefits you are a fraud and just like the ones they have watched on some of the recent TV programmes, and think they are doing "service" to all the taxpayers by reporting anyone, without any proof and without considering the consequences for the person they report !!!
You know you have nothing to hide, so I suggest you get someone to accompany you, request a recording of the Interview and go in there and give them the truth, and quash any malicious lies that may have been phoned in !!!
Who knows, maybe while they are conducting the Full Review, they may discover that you are not getting everything you are entitled to and end up getting a nice little back payment bonus !!
Good Luck AJT and let us know how you get on.