The metaphor refers to the high voltage "third rail" in some electric railway systems — the one that if you touch, you get electrocuted. Not many politicians have suffered political deaths by making proposals against Proposition 13, but in practice, only those from safe districts have put forth any real challenges. In recent years, those bills have been authored by folks like Assembly members Tom Ammiano (fomer San Francisco Democrat) and Assembly member Phil Ting (San Francisco Democrat), Senator Loni Hancock (Berkeley Democrat) and Senator Holly Mitchell (Los Angeles Democrat). Others have largely stayed away from the topic. Even after he won reelection in 2014 for his final term, Governor Jerry Brown has taken a "don't touch" approach in recent years, calling Proposition 13 a "tar baby" in 2015 in the same speech he announced he was not supporting a split property tax roll and stated that "talking about [property] taxes is not a useful topic."
Most of the recent challenges to Proposition 13 these days come in the form of split roll proposals. What is a split roll? It depends what proposal you are looking at, but at its heart, it is some form of disparate treatment between, on one hand, commercial and industrial property, and on the other hand, residential property. Under current law, Proposition 13 limits assessed values for all California property at its 1975 level with maximum 2 percent annual compounding inflation adjustments. Because property value increases have historically outpaced the 2 percent inflation adjustments, those who have owned since 1975 typically have much lower assessed values than the actual market value of their property. And those lower values stay in place until there is a “change of ownership” or “new construction,” but when those events occur, the newly assessed value is then limited in subsequent years to the same 2 percent inflation adjustments. So in this way, all property, commercial, industrial and residential, benefits from Proposition 13. There is also a statewide uniform tax rate of 1 percent.