Critics feel that it is unacceptably difficult to enforce the provisions of the charter, which they say makes charter schools essentially accountable to no one. The basic concept of charter schools is that they exercise increased autonomy in return for this greater accountability. They are accountable for both academic results and fiscal practices to several groups, including the sponsor that grants them, the parents who choose them, and the public that funds them. Charter schools can theoretically be closed for failing to meet the terms set forth in their charter, but in practice, this can be difficult, divisive and controversial. One example was the 2003 revocation of the charter for a school called Urban Pioneer in the San Francisco Unified School District, which first came under scrutiny when two students died on a school wilderness outing. An auditor's report found that the school was in financial disarray and posted the lowest test scores of any school in the district except those serving entirely non-English-speakers. It was also accused of academic fraud, graduating students with far fewer than the required credits. Yet charter-school advocates led a heated and divisive protest against revoking the charter.
In addition, even greater concerns arise when, as in Michigan, many charter schools are run for profit. Many educators worry that education will suffer when funding is split between profit and educational spending, rather than going completely toward teaching as is done in traditional public schools. Studies have already shown many instances of charter schools cutting programs or refusing the educate students with special needs so as to maintain profitability. Charter schools in Michigan, where for-profit charters are common, have largely been poorly implemented and students have performed at a much lower level than their traditional public school counterparts.