Seeking to change Prop 13 is usually political suicide. And so far, it appears that San Francisco County assessor Phil Ting and others who want to create a so-called split roll (by eliminating some of the Prop 13 protections on commercial property) are unlikely to get very far.

Ting has the language right. He’s arguing that he’s merely closing “corporate loopholes” that protect older businesses and allow corporations to postpone reassessments of their property. Fixing loopholes polls well, but the advantage will melt away once voters understand that Prop 13 is at risk.

To win, a split roll initiative needs more than clever rhetoric and framing. It needs a tax cut.

Ting and split roll advocates point out that Prop. 13 “shifted the tax burden to individual homeowners while dramatically reducing California's tax base.” Commercial property owners often structure transactions to avoid the reassessment that would increase property taxes. In San Francisco, Ting writes, most of the property taxes were on the commercial side 30 years ago; now the opposite is true.

If split roll advocates are to stand a chance, they should follow that argument to its conclusion and include a cut in residential property taxes in their initiative.

As a matter of policy, it makes sense to raise property taxes for both residential and commercial property (and reduce them on more elastic things like income and sales). But when you’re talking Prop 13, you’re talking politics. And if you’re going to raise taxes on commercial property owners, you need to balance that with a cut to homeowners.

Politically, a residential tax cut would provide a useful weapon in a campaign. Supporters of the split roll, when confronted with objections, will be able to argue that opponents are trying to prevent California homeowners from getting a break on their taxes.

I suspect split roll advocates won’t do this, however. Their goal is more money for government, not a break in residential property taxes.