Early unofficial returns in the elections for the Philippine National Assembly show a dramatic trend in favor of the opposition. Spokesmen for the opposition, however, remain deeply suspicious that the final official results will give a large - and they say fraudulent - victory to the government party, the Movement for a New Society, known by its Tagalog initials KBL.
Vote-counting for the remaining seats may take days, or even weeks. The longer the counting takes, opposition representatives say, the greater the chances that the election will be fixed.
Ernesto Maceda, the campaign manager of the United Democratic Opposition (Unido), says he is ''confident'' that the government will try to manipulate the election results.
''At the moment,'' Mr. Maceda asserted, President Ferdinand Marcos ''is trying to balance in his mind the damage that will result from foreign press coverage (of widespread electoral fraud) and the damage that could result if he allows 75 opposition people to win.''
In the end, Maceda said, Marcos will disregard the foreign press and the public outcry. One reason the government will try to keep opposition representation in the assembly below 40, he alleges, is that this is the minimum number of representatives required to present an impeachment motion.
''If we get 40 people into the assembly,'' Maceda said, ''we'll definitely file an impeachment motion. Of course it won't win, but it will be . . . a blow to his pride.''
Voting trends calculated Tuesday afternoon by the independent poll-watching organization, the National Citizens' Movement for Free Elections (Namfrel), placed the opposition ahead in 91 of the 157 constituencies sampled. There are a total of 183 seats at stake.
The vote-counting is, however, still in its early stages. Namfrel's trend analysis was calculated by computer on the basis of 31.8 percent of votes cast.
Only two results have actually been announced. In the Manila constituency of Las Pinas Paranaque, the Unido candidate, J. F. Ferrer, was officially proclaimed victor Tuesday afternoon. And in another Manila constituency, the government candidate Ronny Zamora - a favorite of First Lady Imelda Marcos - conceded defeat to his Unido opponent.
Maceda, who was President Marcos's campaign manager from 1964 to 1971, and a Marcos Cabinet minister for five years, claims that Unido has won about 75 seats.
He alleges, however, that the President will try to reduce that number to 40 to 50 seats by ''doctoring'' the results. ''And then he may try to cut our seats down even more by bribing assemblymen to change sides or vote government on key issues,'' Maceda said.
Maceda maintained that tampering with election results would be relatively easy.
The votes, he explained, are counted twice: first in the precincts when votes were cast, then later by a board of canvassers in the local city hall or municipal headquarters. Each board of canvassers consists of three officials and one representative each from the KBL and the opposition. Officials, Unido, and KBL representatives all have certified copies of the voting returns.
''So what will happen is the chairman reads the returns,'' Maceda says. ''They will bear no resemblance to the Unido man's copy. He will object. They'll vote. Unido will be voted down four to one. The reading continues. We go to Comelec (the Commission on Elections, officially an impartial body to oversee elections, but widely alleged to be government controlled.) Comelec will turn us down. We go to the Supreme Court.
''But it could take years, and meanwhile Marcos's man is in the assembly.''