The hunger strike is a time-honored political tactic; its exponents have ranged from the suffragettes to the IRA to the 1989 protesters in Tienanmen Square. But few have been quite as odd as Peter Spencer, the southern New South Wales farmer who claims, somewhat improbably, not to have eaten since November 23 in a protest against land-clearing regulations.

As causes go, the right to chop down native trees is not a particularly inspiring one, and it would be tempting to dismiss Spencer as a nutter being cynically used by the Right in its twin campaigns against greenhouse science and the Rudd government. That conclusion would only be fortified by the views of his brother, Graham, as quoted in today’s Herald Sun, that Spencer’s “problems were only loosely related to land-clearing laws”, that his “land was of ‘marginal’ farming use and that his background was in public relations, not farming”.

Nonetheless, good causes often have unworthy representatives, and there is an important issue behind Spencer’s protest. My friend Chris Berg has a go at teasing it out in yesterday’s Age:

Spencer may not have been physically deprived of his land, but what’s the point if he’s not allowed to farm it? And if Spencer is not compensated for this regulatory taking, how is it much different from legalised theft?

I agree with Berg about the importance of property rights; a society that doesn’t respect property rights is well on the way to denying all rights. But this is only the beginning of the argument, not the end.

Respect for property rights does not require recognition of just any sort of property (most obviously, we don’t allow people to own other human beings), or allowing people to do anything at all with their property (owning a gun doesn’t give you the right to shoot people). Nor do we always think compensation is in order when these rules change: if animal cruelty laws are tightened, I’m not entitled to a refund on the purchase price for my dog now that I’m no longer allowed to mistreat it.

The question of just when we should pay compensation is a deep one, and it’s going to be hard to draw sharp lines. Berg’s example of heritage restrictions is near one end of the spectrum; compensation for slave owners is somewhere down the other end. Where we put Spencer’s case will depend on what we think about land clearing.

If you think clearing native vegetation is the natural and generally beneficial thing to do with land, and that regulating it is exceptional and only due to changed circumstances, then full compensation would be the way to go. On the other hand, if you think that land clearing has generally been an ecological disaster that is still doing great harm to our continent, then you’ll think that people such as  Spencer should consider themselves lucky to have gotten away with it for this long.

Reasonable people may well differ on this, although I confess that I lean more to the second view. The problem is that talk about property rights on its own won’t really help to decide between them.