The new Philippine government believes that former president Ferdinand Marcos and his family misappropriated millions, perhaps billions, of dollars of public funds and that most of the loot is hidden in the United States. The new government is attempting to get it back.

The situation is reminiscent of the flight of the shah of Iran in 1979. The Khomeini government was convinced that the shah and his family had made off to America with at least $25 billion, and demanded that the United States deposit this sum as a ransom for the release of Americans being held hostage. President Carter refused on principle. Besides, our best intelligence was that the shah had taken out at most some $60 million, plus large but worthless shareholdings in Iranian companies, and that most of the money was in Switzerland and not in the United States. In the final negotiations, we did agree to freeze the shah's American assets until Iran could make its case that they had been misappropriated, but hardly anything was found.

The Marcos millions or billions in this country may also turn out to be an iridescent dream. But several legal channels are open to President Corazon Aquino to find out what is here and prove her government's right to get it back. President Reagan cannot issue a freeze order, as in the case of the shah's assets, because he has not previously declared the kind of emergency threat in the area of the Philpines that is the statutory requirement for such an order, and he has no basis for doing so now.

But if the Aquino government can make a preliminary showing to an American court that it has substantial evidence of misappropriation, it could obtain an injunction restraining Marcos and his party in Hawaii from disposing of such assets before the Philpine government has an opportunity to prove it is the rightful owner. This proof could then be developed in a Philippin civil court action against Marcos and his departed retainers, assuming, as is likely, that the Philippine government could successfully serve them with process in Hawaii. (Marcos could not be extradited on a civil charge, and President Reagan has discretion to refuse extradition on a criminal charge.) The Philippine court judgment could then be enforced by an American court against the Marcos party and their U.S. property, so long as the American court satisfies itself that the Philippine trial was a fair one.

The Philippine government could also bring its own civil action against Marcos and his retainers in U.S. courts to recover stolen property located in the United States. In such an action, the liberal American discovery procedures would require the Marcos group and its American financial agents to testify and produce records concerning holdings anywhere in the world.

In any such court proceedings, the Marcos group would not enjoy sovereign immunity, and even if President Reagan should want to, he could do noththe all-embracing grasp of the American legal system. Like other private residents of this country, Marcos and his friends stand exposed to the travails and costs of lawsuits American style. What the Aquino government will get out of it all depends on how much the Marcos clan really got away with and how much they were shortsighted enough to stash within the reach of American laws and lawyers.

Marcos and his friends may also have violated American criminal conspiracy laws relating to the misappropriation of foreign aid, the payment of bribes and the nonpayment of American taxes. The U.S. government is now investigating such charges. Whether this will be a help or a hindrance to the Aquino government depends on how much access the American authorities will allow to the records and other evidence they acquire and when this access is permitted. Our government's "detention" of the property and records the Marcos party carried to Hawaii can also be a help or a hindrance. Because of the unusual manner of the party's arrival, the Customs Service detained these items and is now making an inventory to decide whether they can lawfully be imported. And since the property and papers are claimed by both the Marcos party and the Aquino government, the United States has quite properly decided to leave the ownership issue to our courts. It plans to file what lawyers call a bill of interpleader, which gives the court control over the detained items and the right to decide who gets them.

The crucial question, however, is whether the administration agrees to let the Aquino government have access to the papers pending the court's decision on their ownership or whether the Department of Justice, which may already be reading the papers, will try to keep them to itself until its own criminal investigations are concluded. The date, in Adelaide's immortal line from "Guys and Dolls," could be the "Twelfth of Never." But the administration's record of cooperation with the Aquino government so far suggests a happier outcome.

Aquino can obtain one other personal satisfaction out of the American legal system. Under our Alien Tort statute, which permits one alien to sue another for a legal wrong committed abroad in breach of the law of nations, she and her family could bring a damage action against Gen. Fabian Ver and other Marcos retainers, perhaps even the former president himself, for participating in the conspiracy to murder her husband. Assuming the necessary proof becomes available, the weight of an American court judgment in world public opinion would be of even greater value than the amount of the damage award.