Immigrants seeking the legal right to live in the U.S. are often desperate and helpless, and for that reason immigration law is a booming specialty. Membership in the American Immigration Lawyers Association has tripled in the past decade, to 1,800, and there are thousands of other lawyers who do immigration work part time. Yet despite the efforts of the A.I.L.A. and others to upgrade the field, immigration law has a less than sterling reputation.
"It's a wide-open ball game for exploitation," says Attorney Peter Larrabee, a former officer for the Immigration and Naturalization Service who is head of the A.I.L.A.'s San...