Opponents of immigration reform see illegal immigrants as criminals who will disregard U.S. laws once in the country, writes Frank Fukuyama in the Wall Street Journal, but they are better described as "informal" rather than "illegal." Reform that provides hardworking illegal immigrants with a path to citizenship should be seen as an effort to move people from a dangerous informal system to one based on a rule of law.

There is a widespread perception of a strong link between immigrants and crime. It is common to hear those who oppose immigration argue that the first act illegal immigrants commit on U.S. soil is to break the law-that is, our immigration laws-and that they are ipso facto criminals who will continue to disregard U.S. laws once in the country. Those making this argument are generally steadfastly opposed to any immigration reform that will provide the 10 million to 12 million illegals already in the country any path to citizenship, on the grounds that such an "amnesty" would reward law-breaking.

The association of immigrants with crime is strengthened by the weekly barrage of news about drug and gang violence in Mexico as the government of Mexican President Felipe Calderón seeks to crack down on that country's powerful drug mafias. And long before the Mexican drug war, Americans were threatened by Colombian cartels, Salvadoran street gangs, and other criminal groups from Latin America. Moreover, it is perfectly true that the simple fact of being an illegal immigrant induces one to break further laws: One is reluctant to buy mandated auto insurance, pay taxes, or register businesses for fear of deportation.

There is indeed a huge problem of crime originating in Latin America and spilling into the United States. This is almost wholly driven by the enormous demand for drugs from the U.S. There are many things we can and should do to mitigate this problem, but it will persist as long as that demand remains high.

But the problem of gangs and drug violence should not be confounded with the behavior of the vast majority of illegal immigrants to the U.S., who by and large are seeking the same thing that every immigrant to America has wanted since the time of the Mayflower: to better their condition and that of their families. They are not criminals in the sense of people who make a living by breaking the law. They would be happy to live legally, but they come from societies in which legal rules were never quite extended to them. They are therefore better described as "informal" rather than "illegal."

Understanding this distinction requires knowing something about the social order in Latin America or, for that matter, in many other developing countries. These societies are often characterized by sharp class distinctions between a relatively small, well-educated elite and a much broader and poorer population.

The rule of law exists in places like Mexico, Colombia and El Salvador; the problem is that access to the legal system tends to be a privilege of the well-to-do. The vast majority of illegal immigrants to the U.S. come from poor rural areas, or shantytowns in large cities, where the state-in the form of courts, government agencies and the like-is often absent. Registering a small business, or seeking help from the police, or negotiating a contract requires money, time and political influence that the poor do not possess. In many Latin American countries, as much as 70%-80% of the population lives and works in the informal sector.

The lack of legal access does not make everyone in these regions criminals. It simply means that they get by as best they can through informal institutions they themselves create. The Peruvian economist Hernando de Soto has written extensively about the lack of formal property rights, not just in his own country but throughout the developing world. The poor do not hold legal title to their homes, despite having lived in them for years, because of the insuperable barriers the system throws up to formal registration. So they squat in their homes, constantly insecure and unable to use their property as collateral.

The poor are entrepreneurial and form businesses like restaurants and bus companies, but they are unlicensed and don't conform to official safety rules. They and everyone else would be much better off if they could be brought into the formal legal system, but it is a dysfunctional political system that prevents that from happening.

What illegal immigrants to the U.S. have done is to recreate the informal system within our borders. The Americans who hire them are often complicit in this system by not providing benefits or helping them avoid taxes through cash payments. The gardeners and maids and busboys who participate in this game, along with their employers, are indeed breaking the law. But they are in a very different category from the tattooed Salvatrucha gang member who lives by extortion and drug-dealing.

A comprehensive immigration reform that provides hardworking illegal immigrants with an ultimate path to citizenship should not be regarded as rewarding criminal behavior. It should be seen as an effort to move people from a dangerous informal system to one characterized by a modern rule of law.

We need, of course, to control much better the total number of people coming into the country, which can ultimately be done only through stronger enforcement of employment rules. If we can better distinguish between illegal and informal in our political discourse, then we can begin to concentrate our resources on going after those in the immigrant population who are genuinely dangerous criminals.