expired uk passport for id, ok or not?

There is no absolute answer to that. Ultimately it is up to the employer what id they find acceptable. It is their duty to reasonably satisfy themselves that the person is entitled to work in the UK but exactly how they do that is up to them.

At my firm, we allow an expired passport provided it is not too expired and the picture looks like the person.

Alternatively, for DBS purposes, we can accept a full birth certificate with a NI number.

Page 13 of this document in the link might help.
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/441957/employers_guide_to_acceptable_right_to_work_documents_v5.pdf

andygb wrote: »

I have worked for firms where a passport is required as proof of ID, for money laundering checks/regulations, and it has to be a current, valid passport.

Presumably the firms would allow other ID though? After all, not everyone has a passport. I've never had a ten year one, although I did have a single year family passport over twenty years ago, and was on a group passport for a school trip in 1983 - though neither of those would have been any use for ID.

Deep_In_Debt wrote: »

At my firm, we allow an expired passport provided it is not too expired and the picture looks like the person.

Alternatively, for DBS purposes, we can accept a full birth certificate with a NI number.

Page 13 of this document in the link might help.
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/441957/employers_guide_to_acceptable_right_to_work_documents_v5.pdf

I think the link is broken.
There are 3 "routes" for checking.
Route 1 requires one from the following list
Group 1

Passport
EU National Identity card
Identity Card for Foreign Nationals (ICFN) / Biometric residence permit
Driving licence (full or provisional)
UK/Isle of Man /Channel Islands/EU; photocard
Birth certificate (UK and Channel Islands) - issued within 12 months of date of birth – full or short form acceptable including those issued by UK authorities overseas, such as Embassies, High Commissions and HM Forces
HM forces ID Card (UK)
Firearms licence (UK)
Adoption certificate (UK and Channel Islands)

One of those has to be produced with other documents.

But the online service my organisation uses accepts only a passport or photo driving licence and not a birth certificate issued within the first year of life or any other of the items listed.