LAST week federal authorities disclosed that four cancer charities had bilked tens of millions of dollars from donors. Questions continue to surface about the lack of transparency at the Clinton Foundation. Philanthropy, we’re learning, is a world with too much secrecy and too little oversight. Despite its increasing role in American society, from education to the arts to the media, perhaps no sector is less accountable to outsiders.

The charitable sector is a bit like the Wild West — by design. Foundations have long been granted expansive freedom, on the view that the diversity of America’s civil society is one of the country’s signature strengths, as Alexis de Tocqueville famously said, and that government shouldn’t mess with this magic. Both political parties have been content to impose a minimum of rules on philanthropy.

For example, foundations don’t have to prove that they’re making good use of billions of dollars of tax-subsidized funds, and nonprofits don’t have to identify their donors, as we’ve learned from the Clinton Foundation saga. The law even permits donors to get an immediate tax break for charitable gifts that may sit in investment accounts for decades, never helping anyone. And in many states, the rules that do govern philanthropy are barely enforced, which is why the fraud perpetrated by those four cancer charities was undetected for years.

This lax oversight is out of step with the times and is an invitation to corruption. It also makes it hard to answer the simplest questions about charitable giving, such as what society is getting for the $40 billion in tax breaks that donors receive annually. Were the millions that have gone to the Clinton Foundation, instead of the Internal Revenue Service, well spent? We have no way of knowing.