On SSRN, Professor Leon Trakman looks at Australia's recent policy change on investor-state dispute settlement, and asks, "Investor State Arbitration or Local Courts: Will Australia Set a New Trend?" From his conclusion:
The most profound risk to the institution of investor-state arbitration is one of perception. That perception is that the track record of ISA reflects a history of servicing developed states and their investors over developing states and their public interests. That concern is accentuated by the perception that ISA proceedings lack transparency. Arbitrators are sometimes found to be in conflict ofinterest or seen as failing to make material disclosures, while arbitral awards on occasion are inconsistent in nature and effect. The added perception is that ISA institutions like the ICSID and UNCITRAL are in a state of paralysis and unable to move beyond the status quo. Given these risks, the result may be multi-lateral inertia that leads to a further hazard: ignoring an early signal of a shift away from investor-state arbitration towards home spun domestic courts. No matter how complex, incongruous and self-contradictory that shift may be, it may also have legs that grow over time.
In addition to investor-state and local courts, I wonder whether state-state investment disputes are another avenue. I don't feel like I hear that talked about much as a possibility for enforcing investment rules.