Planning commissions, zoning boards, and city councils in Utah, Missouri, and Tennessee, for example, are currently trying to decide who may, and who may not, live in a residential area designated for "single family" occupancy.  Depending on who wins in these definitional battles, some property owners may have to sell and some renters may have to move.

Those most at risk in these political battles are multiple person households where some occupants are not related to each other by blood, marriage, or adoption.

In Provo, Utah, current law allows a homeowner or renter to live with an unlimited number of relatives, or up to two unrelated people.   A new proposal would declare that only people related by blood, marriage, or adoption may live together in a single family zone.

The Provo City Council is expected to vote on the proposal before May 1.

Meanwhile, a controversy over the definition of "family" is winding through a political process in Black Jack, Missouri.  Last week, the City Council there directed the planning and zoning
commission to review an existing ordinance forbidding more than three unrelated people from living together. 

Black Jack's definition of "family" has been criticized by human rights groups because it has been used against unmarried parents with more than one child. 

In Knoxville, Tennessee, about 50 residents recently attended a forum sponsored by the Metropolitan Planning Commission to draft a new definition of "family" in that community. 

Most of the homeowners asked the Commission to adopt a "family" definition upheld by a United States Supreme Court decision in Village of Belle Terre v. Boraas in 1974.   The Supreme Court concluded that rights of individuals under the federal Constitution are not violated when a city prohibits more than two unrelated people from occupying a home in a single-family residential zone.

Although this precedent may preclude a federal lawsuit, groups of three or more people who are pushed out or prohibited from living together in "single family" zones have other legal arguments they can advance.  They can claim, perhaps successfully, that an unduly restrictive definition of "family" violates their rights to privacy or liberty or equal protection of the law, as guaranteed by their state Constitution.

The California Supreme Court, for example, invalidated a Santa Barbara ordinance prohibiting more than five unrelated adults from living together but allowing an unlimited number of relatives to share a house.  The court ruled that the right of privacy protected the freedom of a group of individuals to live together so long as they were functioning as a family, even if they were not related by blood, marriage or adoption.

Over the years, the highest courts in New Jersey, New York, and Michigan have also ruled in favor of nontraditional households and have invalidated restrictive zoning laws which focused solely on the fact that a group of individuals were unrelated in a traditional sense.  These courts faulted laws which ignored the fact that a group of nonrelatives may be the "functional equivalent" of a more traditional family unit.

In the 1984 case of Charter Township of Delta v. Dinolfo, the Michigan Supreme Court specifically rejected the Belle Terre decision.  In declaring the ordinance unconstitutional under the Michigan Constitution, the court concluded:

"Unrelated persons are artificially limited to as few as two, while related families may expand without limit. Under the instant ordinance, twenty male cousins could live together, motorcycles, noise, and all, while three unrelated clerics could not . . . . The ordinance indiscriminately regulates where no regulation is needed and fails to regulate where regulation is most needed."

These state Supreme Court decisions do not leave cities without tools to address problems of noise, pollution, littering, overcrowding, safety, and traffic.  Laws regulating such issues can be enforced vigorously against offending households regardless of whether the occupants are related to each in a traditional sense.

But such "liberal" court decisions may not prove helpful before more conservative courts in states such as Utah, Missouri, or Tennessee.   If so-called nontraditional families in these places want to win, their best bet is to win in the court of public opinion.

Most people still believe that a person's home is his or her castle.  And they are leary of government regulation of private relationships.

True, the government may need to draw a line in terms of who may live in a residential area zoned for "single family" use.  But that line should be flexible, so that small groups of individuals who are functioning as a single family unit on a long-term basis are not put into the same category as an large group of students who are living together on a short term basis.

If a household considers itself to be a single family, and if it functions like a single family, then it should not matter to local politicians whether the group is related by blood or marriage.  Three elderly friends who share a home, an unmarried couple with children, or a same-sex couple with a foster child, should not be viewed as threats to family living.

The best way for a city council to avoid triggering "culture wars" in their community -- pitting conservatives against progressives -- is to place the focus of a new definition of "family" on function, not structure.