It's only a few lines tucked inside a 200-page bill in the Florida House. But teachers' unions across the state are raising alarms, saying the proposed rule could expose public school teachers to major pay cuts and job losses.

The rule requires teachers' unions — and only teachers' unions — to maintain 50 percent membership among the total number of teachers eligible to be part of their groups or risk getting decertified.

"They don't even try to hide it. They just want to eliminate the teachers' union," said Mike Gandolfo, president of the Pinellas County Teachers Association.

The privatization of schools is the ultimate goal, said Gandolfo, which would be made easier if the teachers' unions are eliminated because "no else is standing in their way."

Pinellas County's union, as well as the one in Pasco, hovers close to the 50 percent membership cutoff, Gandolfo said. In the summers, older teachers retire and new teachers attend orientation, a transition period when membership dips.

"I assume they're going to choose the most nefarious time," Gandolfo added.

The language for the 50 percent rule appeared in a different bill, HB 25, which passed the House floor but had no companion in the Senate, rendering its chances for success fairly slim. The original bill would have applied to all unions except for police and fire.

But the teacher's unions threshold was added this week to HB 7055, the House's major omnibus education bill that addresses numerous issues, from computerized testing to school governance to funding vouchers for bullied students — a major priority for House Speaker Richard Corcoran.

That means a measure that endangers teachers' unions is now tied to a bill rapidly advancing through House committees despite loud protests from Democrats.

"Since when have we come to a place where you don't want individuals to represent themselves?" said Rep. Shevrin Jones, D-West Park, the ranking Democrat on the House Education Committee. "What we can't do is silence the mouths of people."

Earlier this week, Jones vowed to negotiate with Rep. Michael Bileca, R-Miami, the education committee chair, to take the language on teachers' unions out of HB 7055. However, when the bill was passed along party lines through House Appropriations on Wednesday, the union portion remained.

Bileca said the bill isn't targeting teachers, but can only include teachers' unions because it's an education bill and thus can only deal with education issues.

The 50 percent threshold is intended to preserve the rights of the majority, Bileca said.

"A minority leadership … is not a voice for the majority," he said.

He emphasized that because the ideas included in HB 7055 have been "thoroughly vetted" by going through separate committees before they were combined, they were fair game to be packaged together.

This union measure puts yet another strain on the distrustful relationship between public schools and the Legislature, which has spent much of its energy pushing through bills promoting school choice. Last session, a similar mega-bill, HB 7069, was passed late during session. It has since been challenged in court by some school districts.

Tightening regulations on unions have weakened them in other states. In 2011, Wisconsin voted to restrict the bargaining power of teachers' unions and required an annual vote for them to remain certified. That school year, about 11 percent of teachers there left the profession, according to an analysis by the left-leaning Center for American Progress Action Fund.

While the Hillsborough Classroom Teachers Association has said its membership is "well over" the 50 percent margin, its executive director Stephanie Baxter-Jenkins still had misgivings about the rule.

"The teacher's union has been very vocal in some of the horrific things they have done to public education in the last several years and I think this is clearly retribution for vocally opposing the selling off of public schools," she said.

Rep. Manny Diaz, Jr., R-Hialeah, chair of the House PreK-12 Appropriations Committee, said districts will benefit from the new rules.

"Every school district that we talk to, every superintendent they always say they want more flexibility," he said. "This provides more flexibility and it's really a choice for the membership I don't see how this doesn't benefit in any way any side other than the districts themselves."

He dismissed allegations from several union leaders that he would personally gain from a weakened public teachers' unions. He is the Chief Operating Officer for Doral College, which is affiliated with prominent charter company Academica.

Representatives with the United Teachers of Dade, the largest teachers' union in Florida (and in Diaz's district), said its membership is currently just below 50 percent and would be hurt by the new rule if it led to the decertification of the union.

"Thirty thousand employees would lose planning time, there would be no limit on meetings they'd have to attend, no duty-free lunch, they can stay long hours after school and be fired at any moment," said Karla Hernandez Mats, the president of that union. She added that if this bill passes, "many teachers should be prepared to have no job next year."

-Times Staff Writer Jeffrey S. Solochek contributed to this report