On a cool summer night, 36 Managuans sit on rickety folding chairs in front of their wooden shacks vehemently discussing the price of cooking oil. They are attending a meeting of a Comite de Defensa Sandinista (CDS), a Sandinista neighborhood block committee.
To the Sandinista leaders of Nicaragua, these meetings are an example of grass-roots democracy in action. For some of the conservative opposition they are merely another Sandinista tool to control and manipulate the poor.
The CDS meeting in this slum barrio or neighborhood of Giorgino Andrade, like meetings in other barrios and villages throughout the country, suggests that the reality of the neighborhood organizations does not fit any easy categorization.
Observation of the committees makes it clear that they have indeed mobilized poor, powerless people and taught them to organize themselves into groups that work to improve the community from within. They also pressure the government to provide necessary services, and generally get grass-roots input into government decisionmaking.
Equally clear, however, is the important role the committees have in mobilizing neighborhoods for the political purposes of the Sandinista National Liberation Front (FSLN) and generally entrenching Sandinista control over Nicaraguan society.
Giorgino Andrade is a squatters' slum that almost overnight overran empty fields adjacent to a Managua luxury hotel in 1980. Most, though not all, of its residents are very poor.
One resident, Concepcion Jamos, is a married woman who has lived in the barrio since it first sprung up. With her three children, she is one of the 36 adults, mainly women, attending the barrio meeting.
''I have been in the barrio for four years,'' she says. ''They wanted to throw us out, but we fought to stay because we didn't have anywhere else to live. I give thanks to God because I have a place of my own now, not going from place to place like before, with people looking down on me.''
''The CDSs helped,'' she said, ''because when we came here there was neither water nor electricity, and with their struggle now we have water and electricity.''
As Gary Ruchwanger, an American free-lance journalist now writing a book about the committees, observes: ''There is no doubt that in terms of community development and improvement (such as water, electricity, sewage, and roads), house campaigns, and adult education programs, the CDSs have had a very positive impact and reached large numbers of people.''
Ruchwanger estimates that some 500,000 people regularly participate in the committees' various tasks. He believes a much larger number have been the beneficiaries of many of their programs such as adult literacy, child-care centers, and a recent polio vaccination campaign.
In addition to these programs, one of the main roles of the committees today is the administration of a rationing and food system. Two years ago, in response to increasing shortages and bottlenecks, the Sandinistas instituted a partial system of rationing of some basic goods, such as rice, beans, cooking oil, cornmeal, and soap. While these goods can still be found in the markets at prices normally beyond the reach of the poor, most Nicaraguans get their goods with ration cards distributed by the government.
In the poor neighborhoods, these basic goods are distributed through the ''People's Stores'' set up by the Ministry of Internal Commerce. The CDSs distribute the ration cards and supervise the stores and prices and the general distribution process. This has perhaps become the committees' single most important function and main source of influence in the barrios.
For the members of the Giorgino Andrade CDS, the most important issue of the meeting was clearly the food problem. While the discussion of attendance at Sandinista rallies received some interest and the impending opening of a pre-kindergarten school even more, it was only when the discussion touched on food prices and distribution that the meeting really came to life.
''I hope,'' said one woman at the meeting, raising her voice so that she could be heard over barking dogs and screaming babies, ''that all this talk of ideology will be put into practice to control high prices and shortages and that it won't all be just blah-blah or theory.''
The issue of food distribution and prices remains a nationwide problem, one that already has undercut support for the Sandinistas. One of the most important tasks of the CDS block leaders - who are elected by the membership - is to explain that food shortages occur because of the military and economic aggression against Nicaragua by the Reagan administration.
It is the political function of the CDS that draws criticism. In addition to their social functions, the CDSs are a line of communication for conveying and explaining government policy to the people. They often act as revolutionary ''consciousness raising'' discussion centers.
They also play a role in obtaining volunteers for the militia, for coffee and cotton harvesting brigades, and for FSLN political rallies. In a few cases, they have been used to recruit mobs to intimidate political opponents.
They will also, no doubt, play an important role in supporting the Sandinistas during the Nov. 4 elections. One widespread criticism, which FSLN leaders acknowledge as a problem, is that a substantial minority of CDS coordinators withhold ration cards and letters of recommendation from inactive members.
However, the CDS critics' worst fears have not been realized. Most observers believe that they have not in most cases become spies for the revolution, denouncing those who are not firm Sandinistas. They do in some neighborhoods, however, create subtle group pressures to participate in activities and to conform politically.
Many FSLN activists are aware of these problems and speak of the difficulty of mobilizing society for change (which is one of their fundamental tenets) without creating oppressive group pressures.
Ruchwanger emphasizes that for all the problems and abuses, the CDS plays a positive role in transmitting the desires of the barrios up to the leadership, in many cases changing government policy affecting the neighborhoods or getting incompetent officials dismissed.