Taxpayers appalled by the endless cost overruns in the development of the city’s rail system do not have infinite patience. So they would not be holding their breath about promises to unearth any fraud or corruption that could be at the core of the problem.

However, they might be a bit more hopeful about the Honolulu Authority for Rapid Transportation current wrestling match with its cost-control challenges. There are now signs that the need for public input and disclosure about the process is being recognized.

This is the upshot of a report by the Permitted Interaction Group (PIG). It’s a subset of the HART board of directors assigned to review suggestions from the American Public Transportation Association about the authority’s internal auditing practices.

What’s driving this, of course, is the $12.4 billion pricetag, well over what the 20-mile system was projected to cost when work began a decade ago.

The PIG, comprising about half the board members, published a report in which it endorsed 10 changes, including the addition of an internal audit function for HART, to be outsourced with follow-up handled by the board.

Among other potential changes would be the creation of a hotline for fraud and corruption reports — again, one run by an independent provider — that would take reports both from within HART and the general public.

As much as both of these changes are terribly overdue, they would represent positive, welcome steps toward public accountability.

Equally important, though less widely discussed, was the suggested “addition of a process to have proposed resolution or action item amendments available to the board and public.”

Lack of public disclosure has been an issue at various points of this development. In 2018, in the midst of a state audit of the project, the board declined to release unredacted minutes from its executive sessions due to confidentiality of some content. Concern over allegations of mishandled funds also caught the eye of federal investigators, who ultimately subpoenaed records. The results of that probe are eagerly awaited.

But Honolulu should not have to lean on the federal authorities as the only means of bringing facts into the light. This latest report suggests more ways of bringing sunshine to the state’s largest public-works project, and they merit the HART board’s prompt approval.