Yes, according to a recent court ruling
The area where George and Timothy Folk were charged with operating over a congested area. The court documents state the violation occurred near the intersection of Swan Pond Road and Hollida Lane. Courtesy GoogleEarth Larger view
April 29, 2010 — George Folk, EAA 620436, and his son Timothy operate an aerial spraying business from their Martinsburg, West Virginia farm. In 2006 Federal Aviation Administration Inspector George Cooper Towers informed the Folks of complaints from neighbors about low flying, and warned that they must submit a "congested area plan" before flying over any congested area. When the Folks asked what the term "congested area" meant, Towers responded that no precise definition existed. He explained, however, that "a group of…as few as two or three houses . . . may be considered congested."
On July 31, 2006, and September 9, 2006, the Folks flew their plane near the intersection of Swan Pond Road and Hollida Lane in Martinsburg, WV. Because they considered this area uncongested, they did not file a congested area plan before either flight. When neighbors complained about low flying, enforcement proceedings were initiated. Last week a 4th Circuit federal appeals court in Richmond, Va., upheld an initial finding that George Folk and his son, Timothy, flew too low over the intersection. The Folks had argued the area wasn't congested, and also that FAA regulations are unconstitutionally vague, failing to clearly define a "congested area."
The ruling may surprise general aviation pilots since, based on a review of aerial photographs the area the pilots were accused of overflying would be considered by many to be uncongested. The question of what constitutes a "congested area" is not clearly defined, and involves a case-by-case inquiry that considers all relevant circumstances, including the size of the area and number and density of residences, and whether they are occupied or not.
As the summer flying season begins pilots should remember to be cautious of the areas they intend to operate near, and consider tolerances of low-flying aircraft amongst the general populace.
A more detailed legal review of the case can be found here.