The grassroots group that is challenging the validity of Canada's implementation of FATCA with respect to Canadian citizens and residents has released a letter to the U.S. State Department regarding the recent decision to increase the fee for renouncing U.S. citizenship--which is now $2,350. In 2009 the fee was zero. It was introduced in February 2010 (just before FATCA was enacted) and went into effect 6 months later, following Administrative Procedure Act requirements.
You can read the full letter here. In brief, the right to leave a country is not only a universally accepted human right, it is also enshrined in U.S. law. The letter challenges the fee in substance as an unlawful infringement of that right, and in process as a violation of the APA, as the State Department did not observe the procedural requirements for increasing the fee 500% even though it had done so in initially introducing it. Presumably, the group will commence litigation to enjoin the State Department from both legal violations.