The horrendous sticker shock that has hit Oahu taxpayers, who have watched the cost estimates for the Honolulu rail project rocket skyward, is a powerful motivator for elected leaders to seek an exit strategy. Finding solutions is what voters want politicians to do, and in advance of an election year, the pressure to fulfill that desire will mount.

Certainly the Honolulu City Council is feeling that pressure, not the least among them the chairman, Ernie Martin, who has shown interest in running for mayor next year. Even political considerations aside, there is justification to pursue cost controls in the $6.57 billion project.

Unfortunately, the core mechanism Martin has proposed to the Council — a $910 million cap placed on revenues the project would get from a proposed general excise tax extension, with the excess funds directed to affordable housing uses — will cause unintended consequences that ultimately will not serve the taxpayer at all.

The Council today will hear comments on bills dealing with extending the general excise tax surcharge that finances the rail project. The Legislature last session allowed it to be extended until Dec. 31, 2027, five years beyond the original expiration date.

But the tax surcharge, authorized statewide, also must be accepted by the respective county councils. The right action from the City Council would be simply to pass Bill 23, which would change the date when the tax would be repealed. Swift action on this measure will enable remaining work to be contracted in a timely manner, which brings certainty to the process and mitigates risk and the costs associated with risk in contractor bids.

There are a few problems with Martin’s strategy.

He has proposed that instead of dedicating the additional $1.6 billion in tax revenues to the rail project, as the current law requires, the city would cap the rail share of the surcharge funds at $910 million. The balance would go toward construction of affordable housing — undeniably another of the city’s great public needs.

But it’s a need that can be fulfilled through other financing sources rather than by siphoning off money intended for rail. Already the city has a funding mechanism for affordable housing— one half of 1 percent of real property tax revenues goes to the City Affordable Housing Fund for this purpose.

In order to carry out his plan, Martin would need to secure the approval of the state Legislature next session, because lawmakers would need to amend the current restrictions on how the surcharge funds may be spent.

Nobody who watched the drama over the tax extension proposal last session could expect that process to move smoothly at the start of an election year. For a project already beset by delays and overruns, throwing that into the mix surely would hinder more than help.

Avoiding the forces of political influence was the whole reason to leave the principal decisionmaking to the semi-autonomous Honolulu Authority for Rapid Transportation (HART) in the first place.

Further, this would set a bad precedent for taxation policy, allowing the city to divert a state transportation tax surcharge for its own purposes. The transportation tax surcharge for the counties was created as a special-purpose exception to the tax structure, not as the means of providing new revenues for other county uses. The state is guilty of skimming part of the tax surcharge for its general fund; that practice has been wrong and should not be repeated here.

The Council can still send a message about the need for more cost controls to HART. Another element of Martin’s proposal — requiring rail subcontractors to provide detailed reports to the city, as general contractors do — has merit and deserves discussion.

And the Council should press HART forcefully to defend its spending plan when it reviews requests for bonding authorization for the project. That is its oversight role, where this project is concerned, and the Council should exercise that option, rather than burdening rail with more complications than it already has.