The Government's controversial charter school experiment faces more strife, with the principal of the latest school under investigation by the Teachers Council.

As Middle School West Auckland celebrated its official opening yesterday, the trust which operates it said that when it hired principal James Haggett in November it had no idea of the concerns of his former school.

According to a time-line supplied by the Trust, Haggett was hired in November and St Peters made its report to the Teacher's Council in December. Haggett was informed of the complaint on January 14.

Haggett stepped down as deputy principal in charge of curriculum at Auckland Catholic boys' school St Peter's College in June after allegedly misleading the school over the success of the school's academic achievement in Cambridge International Examinations and NCEA. He resigned in August.

The Teachers Council confirmed it had received a mandatory report from St Peter's about Haggett in December. School boards and principals are required to report to the council if they are dissatisfied with any aspect of a teacher's competence or if there is reason to believe there has been serious misconduct.

Middle School West Auckland is one of four charter schools which will open this year under a policy agreed by the ACT Party and the National Government in a post-election deal.

Charter schools receive government funding but are allowed to teach any curriculum and teachers do not have to be registered.

Haggett acknowledged one older allegation, understood to be about the dating of a 2013 exam. In a statement he said: "While at St Peter's College I made an administrative error and compounded that by continuing with the process as opposed to correcting it immediately. It involved nothing financial."

Haggett was made aware of the complaints this year and informed Alwyn Poole, manager of Villa Education Trust, which runs the Middle School West Auckland.

Poole is academic manager at the trust's Mt Hobson Middle School and academic advisor at its South Auckland and West Auckland Middle Schools.

ACT leader David Seymour was among those at yesterday's opening ceremony. Seymour, also under-secretary to the minister of education, said he was aware of the complaint about Haggett.

The council's processes would sort the matter: "The worst thing I could do is to prejudge it if there isn't anything perverse," he said.

Seymour faced criticism in December after Northland school Te Kura Hourua ki Whangaruru, one of five charter schools to open last year, lost nearly a quarter of its roll. An Education Review Office report identified problems including the quality of teaching, management and student engagement.

Villa Education Trust is a charitable Christian trust which operates two Auckland charter schools and one private school, offering small classes, project-based learning and an alternative curriculum in years 7 to 10. The West Auckland school opens tomorrow with 134 enrolled students.

Poole said his wife Karen, the organisation's business manager, had asked St Peter's whether there were any issues with Haggett and if they would hire him again, and were told respectively no, and yes.

PPTA teachers' union president Angela Roberts criticised the lack of government control over charter schools and staff. "It's up to the school to decide how they choose to spend the money, whether they hire qualified teachers, how much they pay their CEO."