Britney Spears ' dad Jamie has been accused of crossing "unfathomable lines" by allegedly secretly recording her in her bedroom while he was her conservator.
Jamie, who recently agreed to step down from his controversial role after court hearings saw her beg for his removal, has been accused in documentary Controlling Britney Spears of taping the singer's conversations with her two sons.
The documentary also claims her text messages and other material from her phone were passed to her father Jamie.
The legal team for Britney, 39, said if true the reports showed Jamie, 69, had "engaged in horrifying and unconscionable invasions of his adult daughter’s privacy".
In a new legal filing, lawyers for the singer said the reports require "serious investigation" and suggested state law has been broken with the recording of private conversations.
The filing states: "Mr Spears has crossed unfathomable lines. While they are not evidence, the allegations warrant serious investigation, certainly by Ms Spears as, among other things, California is a ‘two-party’ consent state."
However, lawyers for Jamie have denied he had access to her "calls, voicemail messages, or texts" in response to the documentary, and said his actions "were done with the knowledge and consent of Britney, her court-appointed attorney and/or the court".
Mathew S Rosengart, the singer’s newly appointed lawyer, repeated his calls for Jamie to be immediately removed from the conservatorship.
He said at a hearing on Wednesday: "As a result of these deeply-disturbing allegations, Mr Spears will inevitably be focused over the next several days and weeks on defending his own interests not his daughter’s (yet again).
"And regardless of the outcome of the allegations, what cannot be genuinely disputed is how deeply upsetting they are to Ms Spears and if nothing else, they magnify the need to suspend Mr Spears immediately."
Mr Rosengart said Jamie will be required to help with the transition to a temporary successor, if he leaves the conservatorship.
He added: "The only thing Mr Spears will ‘lose’ is something he should not have ever had — the ability to further harm his daughter."
Britney has long called for her father to step down from his role as conservator and in a filing last month his lawyers said he was prepared to do so, though no timeframe was given.
In a stunning move earlier this month he asked a judge to consider terminating the conservatorship, a complex legal arrangement usually reserved for the very old or infirm.
Mr Rosengart said in the new filing Spears "emphatically consents to termination of the conservatorship in its entirety, this fall, as it is formally wound down".
The singer recently announced her engagement to 27-year-old actor and fitness expert Sam Asghari.
