Joseph Haggerty may own the most expensive garbage can in America.

Because he kept it in the front yard, not the back, his homeowners association took him to court for violating community rules. After a four-year standoff over whether neighbors could see it behind a shrub, he lost and was ordered to pay $11,978.75 in fines and legal fees.

For Ralph Blevins, the problem was an unsightly toolshed behind his town house in Raleigh, N.C. His homeowners association removed the shed one night, and Mr. Blevins, a 62-year-old civil engineer, protested by withholding $750 in maintenance fees. The association foreclosed and bought the town house at an auction for just $3,000.

About one in six people in the nation, or roughly 50 million residents, lives in a community governed by a homeowners association, from co-op buildings in New York City to suburban subdivisions. Formed to take care of the small tasks that fall through the cracks of municipal government, like picking up garbage and repainting curbs, some homeowners associations are asserting far broader powers, backed by local courts.

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