The Spears family has frequently fought the singer's former manager Sam Lutfi in court, starting with a previous restraining order in 2009.
TMZ reports that Spears made the accusation during a closed-door court session in Los Angeles.
Since 2008, the singer has been under the involuntary guardianship of her father.
Conservators and guardians are often given overbroad authority over conservatees' and wards' lives. Stories of conservatees and wards being isolated or imprisoned by court-appointed protectors are far too common.
Conservatorship Conundrum: You Can Be Reduced to the Status of an Infant With as Few Rights as a Felon
Two types of probate conservators can be appointed. A conservator of the person is responsible for handling the conservatee's health care and other basic needs, while a conservator of the estate is responsible for handling the conservatee's financial matters.
The cold hard fact is that a conservatorship can strip a person of his or her basic freedoms -- sometimes in just a matter of minutes.
If you've postponed doing any advance planning, such as organizing your records, making health care decisions in advance, or doing estate planning, you're not alone.
After a terrifying start to her life with catastrophic childhood epilepsy, Addie has clawed her way to a sense of confidence, grit and burgeoning independence. But there's little time to celebrate her achievement of things that once seemed impossible. We feel compelled to take away some of her rights.
Few 18-year-olds are prepared to handle a large lump sum of money. Laws prevent people from buying alcohol until age 21. It is assumed that people who can't legally buy a beer can somehow be responsible for handling thousands and sometimes millions of dollars.