Updated 4:45 p.m. — Teachers won’t face negative consequences for the next two years if they flunk their annual evaluations because of Common Core-aligned state tests, according to a tentative deal reached today between Gov. Andrew Cuomo and the state legislature.

The deal will create a “safety net” that essentially offers a second chance to teachers who received an “ineffective” or “developing” rating on account of student scores on the new grades 3-8 English and math tests. The new system will allow teachers to have their evaluations recalculated without the state test score component for personnel decisions like termination.

The safety net will be available this school year and the 2014-15 year. State education officials said it would affect about 1,000 teachers statewide, or less than 1 percent of all teachers.

If passed, as is expected to happen as early as tonight, the bill would bring New York into line with how other states are using Common Core test scores. More than 40 states have adopted the standards, but New York had alone in seeking to simultaneously roll out teacher evaluations along with new tests.

That stance has long drawn criticism, even from staunch supporters of the Common Core and of measuring teacher quality. Last week, the Bill & Melinda Gates Foundation called for states to delay using tests in evaluations until after teachers were more familiar with the standards — a move that was widely viewed as putting pressure on New York.

“Just about every state I know of is realizing that doing these things at the same time is very difficult,” said Andy Smarick, a partner at Bellwether Partners who supports new evaluation systems.

Lawmakers made teacher evaluations a top priority as the legislative session drew to a close this month. But the issue has been a longstanding concern for the state teachers union, which first called for a “moratorium” on consequences tied to the Common Core more than a year ago.

The union’s concern mostly focused on the impact that the state’s adoption of the Common Core learning standards would have on teachers, students and schools. The state had already moved to lower the stakes for students and schools, but had resisted calls to do the same for teachers.

NYSUT praised the deal as a “delay on consequences” and President Karen Magee said in an interview that the protections for teachers are what the union had wanted from the start.

“It’s fair for teachers,” Magee said.

Under the provisions, a teacher could still technically be fired because of repeated low ratings. But such a decision would have to reflect ratings based on locally developed student growth measures and a principal observation — not on state test scores.

Officials in Cuomo’s office disputed the idea of a “delay,” arguing that all teachers would be evaluated according to the original rules. They also emphasized that teachers’ original ratings would still be available to parents whose children are in their classes.

The changes are nonetheless seen as a blow to Cuomo, who has said New York’s implementation of teacher evaluations was a signature achievement of his first term in office. But in recent months he began to concede that the Common Core’s rollout had been rushed and signaled that he would be open to some changes.

At a press conference on Thursday, Cuomo said New York’s “teacher evaluation system is moving forward” but acknowledged a need to protect against the possibility of unfair punishment.

In New York City, the provisions will be in place for the first two school years that teachers are working under the new evaluation system. United Federation of Teachers President Michael Mulgrew, who last year joined the NYSUT’s call for a moratorium, applauded the deal.

“Everyone recognizes that the Common Core, while the right direction for education, had a terrible rollout,” Mulgrew said in a statement.

The deal was not universally supported, however. StudentsFirstNY Executive Director Jenny Sedlis said state tests are as reliable an indicator of student learning as exists and that there should be a way to fire teachers whose students don’t show growth.

“School districts need the ability to remove ineffective teachers and it’s impossible to run quality schools with zero consequences and jobs for life irrespective of how children learn,” Sedlis said.

The bill brings to a close a fourth legislative session in which changing the state’s teacher evaluation law, first enacted in 2010, played a starring role. The constantly shifting waters have some observers questioning how much longer the evaluation system in its current form will have credibility with stakeholders.

“I think it’s another barrier to the public seeing the evaluation system as legitimate when it has to be tinkered with every year,” said Aaron Pallas, a professor at Teachers College, Columbia University.

Here is the text of the bill and the bill’s summary.