New Jersey's latest plan to create affordable housing won't work, a state appellate court ruled Thursday. It's unfair, it discriminates against families, and it's based on flawed data.

"The rules frustrate, rather than further, realistic opportunities for production of affordable housing," wrote Judge Mary Catherine Cuff for the three-judge panel.

Once again, New Jersey's Council on Affordable Housing has failed the guiding principles of the landmark "Mount Laurel" rulings - the affordable housing equivalent of Brown v. Board of Education. Families will continue to struggle; the economy may teeter when employers can't find workers. The state must do better.

Gov. Corzine campaigned to create 100,000 affordable homes in 10 years. Assembly Speaker Joseph J. Roberts Jr. (D., Camden) is committed to housing reform. Now the court is demanding a remedy within six months - on a case brought by both builders and housing advocates. The momentum is right for action.

In 1975, 1983, 1986 and 2002, the New Jersey Supreme Court said all towns - urban, suburban, rural - had a legal obligation to provide housing opportunities to people of any income. After two decades, the theory is lauded nationally; practice has fallen woefully short.

That's not news to day-care workers, health aides, security guards, janitors, and firefighters, who increasingly find New Jersey housing prices out of reach.

"Affordable" remains a debate about kids unable to live where they grew up, which is why Ethel Lawrence sued Mount Laurel. But it's also about median home prices soaring past $200,000 in South Jersey; $400,000 up north. It's about rent consuming half of people's income and workers commuting long hours because they can't afford a place near their jobs.

The state's Council on Affordable Housing was supposed to devise rules for municipalities to build or rehabilitate more affordable homes. In its third try, in 2003, it failed miserably.

Under an approach called "growth share," the rules required that municipalities approve one affordable unit for every eight new market-rate homes and one affordable home for every 25 jobs created. Done properly, "growth share" could generate new housing, but COAH used flawed data and left out key calculations, such as redeveloped land, the court said. Plus COAH gave towns too much leeway. They could avoid the obligation simply by limiting growth.

"You want to make sure there's affordable housing where growth is occurring," says George Hawkins, executive director of New Jersey Future, a smart-growth group. "Now, jobs and growth aren't lining up."

COAH discriminated against families with children by allowing towns to meet half of their obligation with senior-citizen housing. While residents over 55 could compete for any available housing, age-restricted housing would exclude other families. That's wrong. Even without this policy, New Jersey is building too many adults-only communities.

The rules falsely presumed that up to 60,000 existing homes would turn over to low- and moderate-income families as more affluent families moved on to bigger or better housing. The idea erroneously depended on a surplus of older, inexpensive housing, which hasn't materialized.

Providing affordable housing remains a legal, moral and economic obligation for New Jersey, not just an admirable goal.