AT FIRST GLANCE , it looks like one of those ugly, awful San Francisco political battles, pitting the city's beleaguered middle class against the even more beleaguered working poor. Sups. Bevan Dufty and Michela Alioto-Pier are asking for a special exemption that would, in the words of its supporters, expand the American dream of home ownership to people who normally can't afford to buy property in the city – without displacing or evicting anyone. Tenant activists say the move – to allow some 374 so-called tenancies in common, or TICs, to be converted to condominiums – will result in a loss of rent-controlled apartments.

But when you cut through the rhetoric, the reality is simple: the benefits of the Dufty-Alioto-Pier plan will go overwhelmingly to people who don't need a special financial favor from city hall – and approval of the legislation will almost certainly lead to more evictions.

But this special-interest bill is just the tiny tip of a big, nasty iceberg bobbing under the surface of local politics. In the end, if the TIC lobby has its way, the city will be increasingly populated by wealthy (and more conservative) homeowners – and the lower-income people (who tend to vote for more progressive candidates and causes) will be gone. The honest advocates of this legislation admit that their real goal is to move San Francisco politics to the right by changing the demographics of the city.

Here's the reality: TICs are the single most powerful weapon in the landlord arsenal against local rent control. Thanks to the state Ellis Act, a speculator can buy a multiunit building full of rent-controlled apartments, evict all the tenants, and turn the place into TICs – making a huge profit in the process. If the city then allows the TICs to be turned into condos, the owners can rent them right out again – and since condos are exempt from rent control, they can charge whatever price they can get away with and raise the rent on the new tenants at will.

There's an incredible amount of money to be made in this scam, and the city shouldn't make it any easier.

As for the poor would-be homeowners, they've already bought property (their share of the TIC), they already effectively own their units (and can sell them to someone else if they want), and they, like everyone else who owns residential property in this city, are seeing their equity (and net worth) rise by unbelievable amounts every year.

There are all sorts of creative, legitimate ways to encourage home-ownership opportunities for people who aren't wealthy (affordable-housing land trusts are our favorite approach). But this giveaway to the speculators isn't one of them. In fact, we like Sup. Chris Daly's idea: he wants a three-year moratorium on all condo conversions while San Francisco figures out how to deal with this policy problem. The supervisors should reject the Dufty-Alioto-Pier approach and take a real, long-term look at preserving San Francisco's nonrich population, as well as its rental housing stock.