Seventeen schools closed amid safety fears were not inspected by the council when their construction was completed, it has emerged.
Instead Andrew Burns, the leader of Edinburgh City Council, revealed the consortium that built them self-certified that they met “all the relevant building standards”.
The Labour councillor spoke out as more pupils at the affected schools returned to classes.
The majority of the 2,000 pupils preparing for exams at the five high schools involved resumed lessons on Wednesday.
Senior pupils from three secondaries were able to return to their usual building as they only had partial refurbishments as part of the Public Private Partnership project (PPP) delivered by the Edinburgh Schools Partnership, while S4-S6 pupils at two other high schools are having classes in alternative buildings but are taught by their own teachers.
But the council announced on Wednesday that practical exams due to take place at the five high schools have been postponed.
As S3 pupils returned to classes at three of the high schools, Mr Burns insisted that the local authority had “undertaken all its legal responsibilities”.
He told BBC Radio Scotland’s Good Morning Scotland programme that “design and the construction standards were the responsibility of the Edinburgh Schools Partnership, who were the main overarching contractor in effect for delivering the facilities”.
While Mr Burns said the council had been “involved in carrying out reasonable inspections and was involved throughout the construction process”, he stressed it was the consortium that had self-certified that the schools met the relevant standards.
The council leader stated: “Under the regulations in place at the time, this is a really important point, under the regulations that were in place at the time Edinburgh Schools Partnership and its agents self-certified to the council, as they were entitled to do so, that the buildings complied with all the relevant building standards.”
He added: “During the construction there was ongoing involvement from the council but the self certification process that was there at the time, quite rightly, quite legally, quite properly, Edinburgh Schools Partnership self-certified to the council that the buildings were compliant with all the relevant building standards.
“So the responsibility lies with the schools partnership.”
When asked if Edinburgh Schools Partnership had been negligent, Mr Burns said: “That will come out in due course.”
But he insisted that the council “will be making sure whoever is responsible for this is held to account”.
The schools were all built or refurbished under the same PPP scheme around 10 years ago but last week the partnership which manages them was unable to provide safety assurances, sparking the closures.
Mr Burns said the schools would have been inspected on an “ongoing basis” since then, but said it was only when more thorough checks were carried out that the faults emerged.
“It’s only since we’ve done the intrusive inspections on the evidence we got last Friday that the latest problems have been discovered,” he stated.
“When councils or the National Health Service, anybody inspects a building they don’t take the walls down, they don’t take the roof off. They’re external, they’re not intrusive.
“It was only when we did the obtrusive and intrusive inspections over the Easter holidays that the faults were discovered.
“If they had been handed to us properly with all the building standards complied too, these problems would not have been in existence, that’s where the problem arose.”
While he said early indications showed “evidence of some fault” at all 17 schools, the council leader added it was too early to say how long each of the buildings would have to remain closed for.