The National Conference of Catholic Bishops voted Wednesday on whether to reject a draft Vatican document questioning the authority of such conferences but first softened considerably a proposed rejection statement.

Earlier this week, as their annual meeting got under way, the bishops' committee handling the issue removed most of the confrontational language from the conference's proposed rejection statement.Then Wednesday, by voice vote, they removed the words "non placet - the draft is not suitable." Several bishops had argued that the phrase, including the formal Latin words, was too blunt, bordering on being offensive to the Vatican.

Still, the proposed final version says elsewhere concerning the Vatican draft, "We do not believe that the working document is suitable as a basis for discussion." In the proposed statement, the bishops ask the Vatican to try again.

The final vote, with two-thirds approval required for passage, began by secret ballot at midday. Results were expected to be announced in midafternoon.

On Tuesday, the bishops said they would publish major statements next year on the deadly disease AIDS and on violence and hopes for peace in the Middle East where "the church is rooted."

Archbishop Roger Mahony of Los Angeles, a leader in both efforts, said, "I feel that we have something to say that could be useful to our own government" as it wrestles with the Mideast situation.

As for the Vatican document, Bishop James Malone of Youngstown, Ohio, another former conference president, argued Wednesday for sending it back and asking the Vatican to start over.

Malone told fellow bishops Monday that the Vatican's "initial working draft is too inadequate" to serve as a base for revision.

"Any accepted first draft sets the stage, with its contents and limitations, for the final document," he said. "A set of misdirections here can skew the final product."

Pope John Paul II has publicly praised the American bishops' most controversial efforts - their national pastoral letters taking issue with Reagan administration policies on nuclear weapons and treatment of the poor in the U.S. economy.

However, Vatican officials take great pains in the draft document to say that national bishops conferences have little real authority as conferences, that the church lodges such authority only in the individual bishops under the pope, the bishop of Rome.