Shares of Acadia Healthcare (ACHC) tumbled 8.61% in after-hours trading on Wednesday following the company's announcement of lowered financial guidance and unexpected legal charges.

The behavioral healthcare services provider revised its full-year outlook, now projecting adjusted earnings per share (EPS) in the range of $2.35 to $2.45, down from previous estimates. This adjustment comes alongside a tightened revenue forecast of $3,280 million to $3,300 million for the fiscal year.

Adding to investor concerns, Acadia disclosed an incremental assumption on legal charges ranging from $4.0 million to $6.0 million, now expected in the fourth quarter. This unexpected development has further pressured the company's financial outlook.

The combination of reduced earnings guidance and unanticipated legal expenses has clearly rattled investors, leading to the significant after-hours sell-off. Market participants will likely be closely monitoring Acadia's next steps and any additional information regarding the nature of the legal charges in the coming days.