The Supreme Court, in a series of astounding and far-reaching decisions over the past few months, has reminded the country of something many might have forgotten: the court has immense power and knows how to use it.

In the course of a dozen weeks, the court has struck down the legislative veto contained in 200 acts of Congress, invalidated 33 abortion laws in the states, sidetracked the administration's effort to deregulate automobile safety and to withdraw tax sanctions from discriminatory private schools, given states their own authority to control nuclear power, and flabbergasted politicians and political scientists throughout the country by requiring better approximations of perfection in the congressional redistricting process.

It all seemed out of character. This court sometimes is better known for flabby and fragmented opinions, for avoiding issues rather than facing them. This year, it sidestepped important reverse discrimination issues in a case involving Boston police and firefighters and the raging controversy over the admission of illegally seized evidence in criminal trials.

One message of the past few months is that the court is totally unpredictable. There are within the court really two courts, maybe three and sometimes eight or nine. They coexist side by side, like Jekyll and Hyde, depending on the case, the reading of precedent or the shift of a single vote.

The other message is that some rulings that seem broad aren't broad, though their consequences may be. Consider the legislative veto case.

Chief Justice Warren E. Burger's opinion in the legislative veto case--which struck down the 50-year-old authority of Congress to "veto" presidential actions--was called one of the court's broadest rulings in a decade. Dissenters said it went far beyond what was necessary to decide the single issue of the case, which concerned an obscure immigration law provision allowing a single house to veto the attorney general's decision to allow a Kenyan to remain in the United States. The court did not confine itself to the one-house veto but went on to strike down two-house vetoes as well.

In fact, the court's simple answer to the one question could not help but answer the other, for it turned not on the number of houses but on the exclusion of the president from the process, a feature of one- and two-house veto provisions.

It was "strict constructionism" with a vengeance. Article I of the Constitution says all bills shall go to the president for his signature, Burger said. The legislative veto provisions exclude that step. Therefore, they are unconstitutional.

As broad as the decision purportedly was, it wasn't really broad enough. It failed to answer a vital question that is now baffling some of the sharpest legal minds in Washington: what happens now to all those laws affected by the ruling? Congress, for example, gave the president the power to sell arms to foreign nations as long as it does not object. It now has lost the power to object. Does the president still have the authority to sell the arms? Is it "severable" from the ruling or not?

Every single affected law will have to be studied for the answer. Anyone who disapproves some executive action under one of these laws is now free to challenge the president's authority in court on the basis of the questions the justices did not answer.

The court did say in INS v. Chadha that the rest of the immigration law survives the ruling. But it went no further. The broader questions were not raised in the case and the court refused to deal with them. It was, in that sense, a narrow holding consistent with the court's traditional approach.

It is impossible to say whether the court would have acted any differently had it been considering arms sales or the War Powers Act, which includes a legislative veto over the use of foreign troops, instead of the immigration law.

The court's handling of redistricting illustrates another phenomenon: how one vote, rather than high legal principle, can produce stunning contradiction. In a case from New Jersey, Karcher v. Daggett, the court said that population differences of less than 1 percent among congressional districts within a state could render an entire reapportionment plan unconstitutional.

On the same day, the court allowed Wyoming (Brown v. Thomson) to retain a state legislative redistricting plan in which one county, with a population of about 3,000, deviated from the ideal population size by more than 50 percent.

Justice Sandra Day O'Connor, who joined the majority in both opinions, said she felt it necessary to explain her participation in "these apparently divergent decisions." She noted that state legislative redistricting traditionally may be more flexible than congressional redistricting and that "equal representation is not simply a matter of numbers."

In fact, the only real difference between the two 5-to-4 cases may have been the shift of a single vote. The majority justices in the New Jersey case (William J. Brennan Jr., Thurgood Marshall, Harry A. Blackmun and John Paul Stevens) formed the minority in the Wyoming case, minus Stevens.

The New Jersey ruling, though important in its consequences, wasn't all that broad either. It did not depart from a 1969 precedent requiring precise equality in redistricting. Brennan, in the New Jersey case, said that equality means equality.

The court's exercise of power appears all the more awesome because everything seems to happen at once. All of the major decisions tend to come down in the last weeks of the term, which probably will end Friday.

Before it ends, the justices are expected to rule on the constitutionality of tuition tax deductions for parents of private school students, the legality of home videotaping and of sex-based insurance tables and the procedure for delaying or halting executions.

The deluge stems from the court's rhythm. It hears most of its cases in the first seven months of its term and issues most of its opinions in the last three months.