Generally speaking, the benefit of the mandatory arbitration provision is that it provides certainty to taxpayers that their double taxation will be resolved. Without the finality of mandatory binding arbitration, the mutual agreement procedure itself only provides that the competent authorities, which in the case of Canada is the Canada Revenue Agency, endeavour to resolve the disputes. Inevitably there end up being a few cases where there is difficulty in resolving those disputes, or when the time frame can be quite long to resolve those disputes. One of the main benefits of tax treaties is to try to encourage trade and investment and to provide certainty for taxpayers and to ensure that they don't end up in a situation of double tax. Those are the significant advantages.
Canada has had mandatory binding arbitration in the convention with the United States since its 2007 protocol. The binding arbitration entered into effect in 2010. It has been considered by both the Canada Revenue Agency and taxpayers alike to be very advantageous in ensuring that disputes are resolved.
In terms of some of the disadvantages, not all of the countries—in fact, only a subset of the countries—are willing to sign on to binding mandatory arbitration. I think to date it's under 30, between 25 and 30, countries that have agreed to binding mandatory arbitration.