In Montgomery County, there is a private 28-person police force that, in the evenings, rides Metrobuses paid for by Maryland taxpayers. If the riders appear to the police to be undesirables, the officers forbid them to leave the bus inside the Leisure World retirement community. In the morning, this force forbids the residents of nearby subdivisions to use those same stops to board Metrobuses. The officers have the right to carry guns and make arrests.

In Reston, the Regency Square Cluster Association fines its residents $50 if they fail personally to help clean the neighborhood on the last Saturdays of April and October. If the fine is not paid, the association has the right -- so far unexercised -- to slap a lien on the offender's house and, if desired, sell it at auction.

The Metropolitan Washington Airports Authority has $1 billion in bonding authority and a chairman who muses about pumping water from the Shenandoah River over the Blue Ridge Mountains, down the center of I-66 and into the Occoquan Reservoir to save Northern Virginia from thirst.

These are only three of more than 2,000 shadow governments that exist in the Washington area. Nationwide, their like has become the largest form of local government in the United States.

These shadow governments levy taxes, regulate behavior, adjudicate disputes, provide police protection, plan regionally, channel development, enforce esthetic standards, build roads, fill potholes, remove snow and provide recreation, and they are the driving force behind the hottest social service in the United States today -- day care.

They are central to a new American society in which office parks are in the child-rearing business, parking-lot officials run police forces, private enterprise builds public freeways, and subdivisions have a say in who may live there.

"The privatization of government in America is the most important thing that's happening, but we're not focused on it. We haven't thought of it as government yet," said Jerry Frug, professor of local government law at Harvard.

These shadow governments have powers far beyond those ever granted governments in this country. They can regulate the colors of a person's living room curtains, prohibit the organization of everything from a Rotary Club to a Boy Scout troop, and specify what, if anything, a person can park in his or her driveway. Nonetheless, the names of their leaders never appear on a public ballot, and they are frequently not subject to the checks and balances of the Constitution.

What these governments really are, say urbanolo- gists, are highly original, locally invented, special- purpose attempts to stave off anarchy in the cities that are emerging nationwide in places that used to be suburbs. Typically, the newer the emerging city, the less likely it is to have traditional urban government. Therefore, the more common and powerful are the shadow governments that people create.

Like all solutions, critics say, these vacuum-filling shadow governments create problems. For example, how does a resident fight city hall if he or she cannot find it? How does he or she "throw the bums out" if there is no elected council?

In the Washington area alone, as many as 14 emerging cities were identified in a March 8 Washington Post survey. Emerging cities have more jobs than households, have more people commuting into them than out, and are perceived as destinations for entertainment and shopping as well as jobs. Examples of emerging cities include Tysons in Virginia, which is bigger in terms of jobs than downtown Miami, and Rockville/Gaithersburg in Maryland, which is bigger than Baltimore. (See map below.)

In its continuing examination of emerging cities, The Post asked urban affairs, legal and government specialists, "Who runs these new cities?" The cities are rarely incorporated, never match political boundaries, and sometimes do not even appear on conventional maps.

"We go into these new cities and ask, 'Who's the mayor? Who's the city council?' They never have any!" said Ralph Stanley, former head of the federal Urban Mass Transportation Administration.

It turns out, nonetheless, that they are governed -- in most cases by shadow governments.

The Post survey found three types of shadow government, each of which is examined in the accompanying articles:Private-enterprise shadow governments, such as homeowners associations.

Public-private partnership shadow governments, such as the coalition of developers and political officials that tackled the Tysons road shortage. Arms of conventional public government with highly unconventional powers, some of which have the potential to become regional governments.

Walter Scheiber, executive director of the Metropolitan Washington Council of Governments, provided a four-part definition of government, shadow or otherwise. A government: Assesses fees to support itself. Legislates. Modifies its residents' behavior. Has the power to coerce to accomplish the first three tasks.

In addition, the leaders of shadow governments are never directly accountable to the voters at large in a public election and are frequently not subject to the constraints on power that the Constitution imposes on elected governments.Free to Make Own Rules

For example, the Constitution prohibits governments from enacting laws abridging freedom of speech. Because shadow governments are usually not regarded legally as governments, they are generally free to make their own rules. There are about 110,000 private-enterprise shadow governments alone in the United States, deeply touching more than 20 million Americans.

"Picture an America in which you live in a condo community, private, and then work in one of these {emerging city} places," said Harvard's Frug. "You can privatize the schools, security, garbage collection. What would be the realm in which democracy would then operate? There's no reason Tysons has to be run by the board of directors. Democratize Tysons Corner!"

Shadow governments are usually democratic, after a fashion. But, significantly, they rarely have much use for the principle of one-person, one-vote.

For example, the shadow government that runs the 1,016-home Montebello condominium in Fairfax County does hold elections, but they are not subject to the Voting Rights Act. Only property owners may vote, not just any citizen over 18 as in a public election. What's more, the vote is weighted to five digits to the right of the decimal point according to how much a person owns. The owner of a one-bedroom place gets 0.06883 of a vote. The owner of a two-bedroom place with a den gets 0.12350 of a vote.

This is a one-dollar, one-vote democracy. It hearkens to the early days of the republic when the vote was reserved for white male property owners who were viewed as having the biggest stake in how the society was run, scholars said.

In fact, those interviewed for this article repeatedly volunteered how strikingly similar shadow governments are to the legal and governmental structures that served the republic in its early years.

"It's a return to the 19th century in which there was no legal distinction between a city and a private corporation. All had the same powers and restrictions. Railroads could take your land and pay you for it without your consent. You could do anything privately that you could do publicly," said Frug.

Shadow governments "move into vacuums," said Edmond F. Rovner, special assistant to Montgomery County Executive Sidney Kramer. "They get into one issue, and they've got a professional here and a technician there. And then they'll give you an opinion on what you're ordering for lunch. And before you know it, they've named two of your children. They eat up power, like the science-fiction movies. They eat living things and derive power from what they've ingested. They dump on people who appointed them and develop an independent power base. In our county, that's the Park and Planning Commission."

The members of the Montgomery County Planning Board of the Maryland-National Capital Park and Planning Commission "were the one-eyed man in the land of the blind. 'We have the numbers, the formulae, the charts, the tables,' " said Rovner. "What kind of county do you want? What kinds of people? That's what you're determining when you determine lot size. Those are valid decisions for a community to make. But the decisions ought to be made by people who owe their power to the consent of the governed. Park and Planning is neither elected or anointed. Park and Planning is answerable to nobody." Transportation Is Key Issue

It is no coincidence that many of shadow governments were formed to address the problems of the automobile. "Water and sewer were the controlling things for development," says Montgomery County's Robert S. McGarry. "Transportation is the issue now."

McGarry has created shadow governments for Bethesda and Silver Spring, called "Urban Districts," from his position as head of the Montgomery County Department of Transportation. From 1977 to 1983, he ran the sewer-building Washington Suburban Sanitary Commission.

"The Washington Suburban Sanitary Commission used to be a shadow goverment," said Rovner. "But now the sewer lines are almost all in place, so they don't play the kinds of games they once did. Their act is so cleaned up, they're no longer powerful."

Many shadow governments are markedly more efficient than the public kind. "There's no question that they're faster and cheaper. The incentives for prompt performance are stronger in the private sector," said Robert C. Ellickson, a professor at Stanford University's law school.

"People can coordinate with one another to their mutual advantage more than is generally recognized," Ellickson continued. "Take the English language. The people living on the island of Great Britain came together and just created a language. Nobody was put in charge. People are now coordinating in a sophisticated way. I think it's terrific that property owners paid for these roads. The right people did it. And they did it cheaper. This is not a calamity. This is a terrific thing."

But because shadow governments are usually created specifically to produce goods and services for those who can afford them, they rarely consider the concerns of the poor. "These are governments by the wealthy for the wealthy. It is plutocracy, not democracy," Frug said.

Shadow governments also disturb some experts because of their lack of accountability to the larger society. "They're setting up internal courts. Due process is not required. The 14th Amendment {which guarantees equal protection and due process for all} does not apply," said Douglas Kleine, research director for the Community Associations Institute, a group that represents various kinds of private shadow governments.

"The application of the 14th Amendment would cause all kinds of things. It would subject the board of directors to the Voting Rights Act. In Reston and in Burke, you're elected by district {to the community association}. If the 14th Amendment applied, and you want to redraw those lines, you'd have to go to the Justice Department. You couldn't have one-dollar, one-vote, or one-house, one-vote.

"The First Amendment? The association newsletter is a house organ. It's just like a company newsletter. Editorial guidelines usually include the statement that this isn't a First Amendment vehicle. It's there for us to communicate with you, not you to communicate with each other."

Defenders point out that if the larger society finds the actions of these private governments objectionable, it is not without recourse. Covenants such as those prohibiting house sales to blacks and Jews have been readily thrown out when challenged in court. At the same time, these proponents say, as private corporations, shadow governments have as much right, for example, to print what they choose as does The Washington Post.

What critics find ominous is that shadow governments have a dual nature, with private freedoms and public responsibilities. In effect, critics ask, should shadow governments be so unrestrained?

"Where is the envelope for democracy?" mused CAI's Kleine. "That's a good question." Shadow governments, he said, "are the ones providing the most visible services to people. Recreation. The architectural control powers are very similar to zoning and health code kinds of powers. Providing police forces in some situations. More rarely they provide fire departments.

"They exist where local government doesn't have the capacity to provide services."