The owners corporation is concerned the government won't challenge Morris Construction Corporation's bid to have an order to complete rectification order at the Eyre Street complex thrown out.

The government has stressed that is not the case.

The owners' fears were sparked by a letter last week from the government solicitor to their lawyer, which advised that Construction Occupations Registrar Ben Green would not take an "active role" in the ACT Civil and Administrative Tribunal case.

In his letter to the owners' lawyer, government solicitor Avinesh Chand said the registrar - Mr Green - did not consider it "necessary or appropriate" to be actively involved in the case.

Mr Chand said it might "prejudice his position" in a separate Supreme Court case relating to alleged defects at Kingston Place's stage two complex.

In that case, the owners are taking legal against Morris and five others parties responsible for the design and construction of the 120-unit complex, as well as the ACT government, which approved the units for occupancy.

The owners corporation's chair, John Grant, reacted furiously to the letter, believing it signaled the government's intention to abandon the case.

If Morris wins the appeal, the rectification order would be thrown out, meaning more than 230 props installed to prevent parts of the building from collapsing could be removed.

Mr Grant fired off an angry missive to Chief Minister Andrew Barr soon after he received the government solicitor's letter, imploring him to instruct Mr Green to continue defending the case.

He said it was the job of the regulator - not the owners - to argue for the rectification order to be upheld, as he accused the government of having "no real commitment" to holding builders accountable for poor construction work.

Mr Green strongly disputed The Canberra Times' report suggesting the government was backing away from the appeal.

He said as the independent regulator, his job was to ensure compliance with building rules.

He was not allowed to advocate for either party in a dispute. That was what was intended to be communicated in Mr Chand's letter.

In the case of the Kingston Place dispute, to which the owners are a party, Mr Green's role is to argue that the rectification order should be upheld.

"Far from 'backing away' or 'abandoning' property owners of Kingston Place apartments I have and will continue to assist the tribunal as it reviews the decisions to issue the rectification orders around defects at the building," Mr Green said in a statement.

"We will be defending the decision to issue the rectification orders and will ensure that all relevant facts and documents are before the ACAT. We will make relevant submissions regarding the interpretation and application of legislation."

The government was forced to urgently step in and arrange for the steel props to be installed inside the Kingston Place complex, after Morris refused to complete the work required under the emergency rectification order.

The props are designed to prevent the building's columns from "punching through" the concrete slabs. Access Canberra inspectors had feared that without the supports, the building could suffer "catastrophic" structural defects which rendered the complex unlivable.

The construction company has repeatedly stated its expert advice had determined the complex was structurally sound, and that the support props would cause further damage to the building.