A watered down bid to let public school teachers take part in student-led prayer during school time won final approval Friday night.

The plan, Senate Bill 512, originally would have allowed teachers, at the invitation of students, to take part in prayer sessions if parents and guardians submitted a signed request for them to do so.

That version breezed through the state Senate 29-0 on April 26.

But the state House, worried about the possibility of lawsuits if the legislation became law, narrowed the proposal.

Under the House-passed version, teachers would only be permitted to "quietly bow" during a student-led prayer session as a show of respect and deference to what the students were doing.

House members took the action after state Rep. Alan Seabaugh, R-Shreveport and others predicted the original plan would trigger a lawsuit from the American Civil Liberties Union, and cost school districts thousands of dollars in legal fees.

House members approved the narrower version 99-0.

The bill was sponsored by Sen. Ryan Gatti, R-Bossier City.

Efforts by a House-Senate negotiating committee to hammer out a compromise on the final day of the session failed.

Rep. Rob Shadoin, R-Ruston, who handled the bill in the House, some members of the House are convinced "even though there is no case law that they can cite" passing the bill would "be opening up yet another attack and cost the state to have to come and defend it."

"I don't agree with them but nonetheless they feel strongly about it," Shadoin said.

Two members of the negotiating committee, Reps. Nancy Landry, R-Lafayette and Rick Edmonds, R-Baton Rouge, declined to sign what Gatti hoped would be a compromise agreement that could then be voted on by the House and Senate.

In an interview, Landry said even House leaders who normally back such measures opposed Gatti's, including Edmonds, a longtime Baptist minister. 

"I am deferring to them on this," she said. "We have a constitutional law expert and a pastor both saying there are some serious problems with it."

"Like I told the author, I don't think it would have passed the House without the amendment that the House put on it," Landry said. "He wants to take that amendment off."

That amendment revamped the Senate-passed bill, adding the "quietly bow" language and removing the signed form provision.

Landry is chairwoman of the House Education Committee.

Gatti was in the House chamber shortly before adjournment trying to convince skeptical House members to go along with his plan.

Shortly before 8 p.m. he said he was still working on getting his version of the bill agreed to.

Unable to reach agreement, Gatti agreed to go with the House version moments before adjournment, winning Senate approval 28-1.

Follow Will Sentell on Twitter, @WillSentell.