“The political pressure groups who continue to attack the four specialized high schools intend to eventually destroy these schools and their specialized status in science, mathematics, music and art,” wrote Burton G. Hecht, a Democrat from the Bronx who sponsored the bill in the Assembly. The Senate sponsor was John D. Calandra, a Bronx Republican.

The bill was endorsed by the principals whose schools would be covered by it: Stuyvesant High School, the Bronx High School of Science, Brooklyn Technical High School and LaGuardia High School of Music and the Arts.

“Attacks against the specialized high schools invariably get much attention in the news media,” Louis Weiss, the acting principal of Brooklyn Tech, wrote. “This tends to drive more middle class out of the city and many gifted children into parochial and private high schools.”

Among those opposing the bill were the schools chancellor, the board of education and Mayor Lindsay. On behalf of the school system, the lobbyist Peter A. Piscitelli wrote that the chancellor did not intend to change the use of a competitive exam, but wanted a committee to study serious charges “that the examinations discriminate on cultural grounds, against Negro and Puerto Rican applicants.”

Regina Rosenthal, a student at Bronx Science, wrote to Senator Calandra that she had come to question the admission policies. “I know many black and Puerto Rican students from my former junior high school who, if accepted at Bronx Science, could have benefited greatly from our educational facilities,” she said. “I know that everyone at Bronx Science could have benefited greatly from these students.”

Without deep hearings, study or consideration of any changes, an admissions moat was dug at high speed by the legislature nearly a half century ago. At the time, white students made up close to 90 percent of the specialized schools; today, they are fewer than 20 percent. Most students are Asian. The number of black and Latino students has risen and fallen, but has never come close to keeping up with their presence in the city schools. At Stuyvesant, the most competitive of the schools, only 10 black students received offers this year. The specialized schools are far from bastions of privilege, dominated by immigrants or the children of immigrants.

Mr. Carranza has dismissed the concerns of Asian groups that their children would lose seats if he is able to eliminate the test and rely on factors like class rank. “I don’t buy into the narrative that any one ethnic group owns admissions to these schools,” he said in a television interview.