Britney Spears testimony about her conservatorship raises serious questions

Had it not been for this pop music star, the issue of conservatorship would probably not have gotten the public attention it deserves. A conservatorship is a very serious restriction on the freedom and life of an individual human being.

How was it possible that this forced conservatorship was in effect for about 13 years for this young woman?

How often and how did the courts review this conservatorship in the best interest of the conservatee?

How easy is it for e.g. a conservator to abuse such a court-appointed conservatorship?

How many people in the United States live under such a conservatorship? 

Here are some excerpts from Time magazine article "How Britney Spears' Case Could Change the Future of Conservatorship" about this subject: 

1. "There is limited data on conservatorships, but a National Council on Disability report estimates that at least 1.3 million Americans are under guardianship. Once people are under a conservatorship, there can be periodic reviews, but the process varies by state and there is little oversight."
2. "Conservatees don’t have to lose all of their freedom. In California, for example, where Spears’ case is located, the system is supposed to favor limited conservatorships and give the conservator only those powers that a judge determines are truly necessary. ... However, the National Council on Disability has found that most guardianships for people with disabilities go way beyond that and give all of the conservatee’s rights to the appointed conservator. ..."
3. "In 1927, the Supreme Court ruled in Buck v. Bell that it was constitutional for the state of Virginia to forcibly sterilize a “feeble minded woman” for the “welfare of society,” and this kind of practice continued for decades. States have stopped allowing this kind of sterilization, and most have extra protections before someone under conservatorship can be sterilized, but Crane argues that Spears’ forced IUD constitutes reproductive coercion and should fall under that category as well."
4. "Increasingly, advocates are promoting the model of “supported decision making” instead of conservatorship. Since then, 12 states and Washington, D.C. have recognized supported decision making as an alternative to guardianship, and there are movements in most states to bolster the model, ..."