A small group of activists and local residents gathered last night in the community room of Robbins Library for a civil but at times contentious forum on the state's affordable housing law, Chapter 40B.

The law, formally known as the Massachusetts Comprehensive Permit Act, exempts developers of residential properties from zoning laws regarding requirements such as density, lot size and height, in exchange for long-term affordability restrictions on at least 20 to 25 percent of the housing units. It passed the legislature in 1969 by a single vote.

The law only applies in municipalities where less than 10 percent of the housing meets the state standard for affordability — 80 percent of median income — but few communities, mostly larger cities, meet that bar. 

According to a fact sheet published last year by the Citizens' Housing and Planning Association (CHAPA), a nonprofit that supports the development of low-income housing across the state, the law was intended to assist in the development of affordable housing by "reducing unnecessary barriers created by local approval processes, local zoning, and other restrictions."

But critics say 40B allows greedy developers to override the wishes of citizens and forces high-density development into neighborhoods where it is neither welcome nor appropriate. They also contend that it is ineffective in actually increasing affordable housing to the level needed.

"The parallel I like to use is that at the same time that we enacted 40B — 1969 — Montgomery County, Md., enacted their affordable housing law," said forum organizer John V. Belskis, the chair of the Coalition for the Repeal of 40B and an Arlington resident and Town Meeting member.  

"And it [the Maryland law] had two great things in it, which we've never gotten here and no one wants to put here, and that's inclusionary zoning and perpetuity of the developed units.They produce 15 percent more affordable housing than what we do in Massachusetts, and they can't spend the money they've gotten back from developers that wanted to do in-lieu-of payments."

The coalition favors measures such as inclusionary zoning, which doesn't allow developers to override local zoning but does require that a certain percentage of new development be affordable.Inclusionary zoning was adopted locally by Arlington Town Meeting in 2001.

Craig Chemaly, director of the Chelmsford-based Slow Growth Initiative, helped Belskis lead the forum and noted that the coalition had originally worked for reform rather than repeal but had given up on that goal.

"I wish that we could simply reform 40B or put something better than 40B in place before it's repealed," said Chemaly. "But the problem is that … developers make so much money off of Chapter 40B that they refuse to allow the implementation of a system that really does create affordable housing while 40B is in place."

After a short introduction by Belskis and Chemaly, the forum became an open discussion of the merits and intricacies of the law.

The handful of attendees consisted mostly of people well-informed and vocal in their views on the law, including David J. Levy, executive director of the Housing Corporation of Arlington; Town Meeting members John L. Worden III and Dr. Patricia B. Worden; and a woman who introduced herself as a board member of CHAPA but did not give her name.

Belskis and Chemaly offered a variety of reasons they felt the law is ineffective and that other policies were superior, saying that Massachusetts today rates 47th in the nation in housing affordability despite 40 years of Chapter 40B.

A young man who lives in Somerville and asked that his name not be used told Chemaly that he had grown up in suburban affordable housing and was confused by the logic of the coalition's arguments.

"Honestly, I'm really confused as to whether this is about affordable housing or stopping growth," he said. "You've got a lot of anti-city messages there and then you say you're for affordable housing, but I'm not hearing anything that this is stopping affordable housing. I'm hearing a lot of correlation and causation mix-ups. I'm really unconvinced and confused and honestly a little bit insulted that the kind of house that I grew up in is being a bit demonized tonight."

"I guess if you grew up in a house that was built in a high-density complex in a residential neighborhood, I'm going to demonize it," Chemaly replied.

Monday's forum in Arlington was the last of a series the coalition has conducted throughout the state. Belskis and Chemaly said they had been successful in their petition drive and an initiative for the repeal of 40B will appear on the ballot in November.