A bill reforming Pennsylvania’s backwards teacher furloughing system headed to the desk of Gov. Tom Wolf last week. And while it’s clear that the governor, who vetoed a similar measure last year, is less than pleased with the system being proposed by state legislators, he should hold his nose and sign it into law.

Not because the system being proposed is perfect — far from it. But because doing nothing would be even worse.

Pennsylvania is one of only six states that bases teacher layoffs on seniority alone. Failing yet again to change that broken and outmoded system would be a serious mistake. When ineffective teachers are allowed to stay in school while more effective teachers are shown the door simply because they have fewer years of service, the system needs to be reformed.

Being able to show failing educators the door is undoubtedly a good thing. But who decides which teachers are failing? State officials who can’t design a usable standardized test, but want people to trust their new and unproven teacher evaluation system? School board members? Building or district administrators? Parents? How about the kids themselves?

Part of the problem with rooting out incompetence in the classroom is that there’s plenty of incompetence outside of it as well. And we’re not convinced that the General Assembly’s “new-and-improved” teacher evaluation system — which critics slam as too reliant on student performance on state exams — is the best solution.

But it is a solution, and the current system is demonstrably a bad way of doing business based on a 2011 study that found seniority-based layoffs disproportionately hurt students who live in poor communities. We have a few of those here in Butler County.

Here’s some things that seniority-based layoffs do accomplish, according to the 2011 study by the University of Washington’s Center for Education Data and Research:

n Lead to districts laying off more teachers to meet budget goals, because junior teachers are paid less.

n Lead to some districts laying off teachers in high-demand and hard-to-fill areas like special education.

n Lead to estimated student achievement drops of between 2.5 and 3.5 months of learning per student when compared with performance-based layoffs.

The top priority should be staffing our schools with the most talented and best-performing teachers, and seniority-based layoffs do not accomplish that goal. Doing nothing is not an option.