An electrician is defined as "A person who possesses sufficient technical knowledge, relevant practical skills and experience for the nature of the electrical work undertaken and is able at all times to prevent danger and, where appropriate, injury to him/herself and others." he does not need any qualifications, it is actually a competent person which is higher than skilled.
We would hope today they would have done some courses, and will have passes some exams, but they don't need to have done to call themselves electricians. In the past the Union would vet people and we had a closed shop with many firms, and if the Union did not rate your skills you could not work, but the government made this illegal.
It was replaced with the domestic market with scheme providers, however no one can force an electrician to join one, that would be illegal, as it would then be a closed shop, and we have to have multiple scheme providers for the same reason, and again due to the law passed to stop closed shop they are not allowed to share information about electricians between them. However they can and do allow member electricians to advertise that they are members. And it is illegal for a non member to display any logo or name to show they are members when they are not.
Scheme membership allows the electrician to notify work though the scheme which is very much cheaper that doing it through the LABC, however the electrician is not the person responsible for notifying unless they do display some logo, rather a silly situation, specially since even non members can do the notifying for the owner, so the home owner can easy not realise it is up to them to notify.
If the electrician is working with no intention to con the owner, he will know the owner needs to submit the installation certificate to the LABC, so he clearly will issue one, there are cases where it does not make financial sense for an electrician to be a scheme member, one needs to do a far bit of notifiable work to be worth while, work for the disabled is free to notify, and commercial work does not need notifying and what needs notifying depends on where you live.
An EICR and the EIC are not legally required, the whole of the BS 7671 is not legally required to be followed, although is can be used in a court of law, an electrician has been taken to court by trading standards for poor workmanship, the same applies to any trade, but there is since that law banning closed shop, not law to stop anyone claiming to be an electrician, there are some professions where the law does stop people saying they are members like the police for example, but not electricians.
So you need to show the work was not to a professional standard. I would think it hard to show leaving the earth sleeve off means not to a professional standard, not good practice, but not really enough to cause problems, in most cases.
So when you sell the house you will be asked if you have had any notifiable work done, and if so to produce the certificates these are either compliance or completion certificates, the EICR and EIC are normally provided but there is no requirement for them, I misplaced my certificates for my mothers house, and tried to get replacements, the LABC who should have copies, told me it would take 4 months and would cost however long it took the council worker to find them. In other words go away and don't be silly, I told the solicitor who said no problem we can take our an insurance. Not sure how that works, as then I found the missing certificates.
Looking at them I realised there was very little to say which certificate covered what, I had three, one for a rewire, one for the kitchen, and one for bathroom, but nothing written on them to say exactly what they covered, I knew as I was involved with the work, but there was nothing to tell a stranger what related to what, with the completion certificate there was nothing at all to relate it to the EIC which I had raised and the completion certificate had been issued as a result of what I had written. And clearly the LABC could not be bothered.
So unless the work is sub-standard then little anyone can do.
So if one wanted a new circuit, say a supply for a boiler to be installed. The scheme member would issue a certificate for that work, so you would then have a certificate, not for the work done by the other electrician, but he would need to work in the consumer unit, so would highlight any faults, and the solicitors would be non the wiser.
At least mine weren't, I was given an EIC which showed a collection of circuits, but on moving in, found it only related to the old garage which had been turned into a flat, there was no certificated for the main house, and if done before 2004 they are not required.
The case brought by Pembrokeshire County Council Trading Standards and heard by Judge Huw Rees at Merthyr Tydfil Crown Court on Monday, September 20, 2021 where the electrician had not displayed a warranty of skill, is the only one I know of, but it was the electrician taken to court not the person selling the house. I was quite surprised, I would have thought the buyer would have needed to take seller to court and the seller take the electrician to court as clearly no contract between the buyer and the electrician.