Palm Desert police conducted a battery investigation at the scene at about 1 a.m. on Dec. 12. "The victim desired prosecution," says Sgt. Joe Borja of the Riverside County Sheriff's Department. "The incident is being investigated as a misdemeanor."
A source close to Lohan, 24, says the actress denies pushing the woman first. The staffer scolded Lohan for allegedly returning past curfew after spending the evening at a local bar, TMZ reports.
It isn't known whether she had been drinking; the Betty Ford Center regularly tests patients for alcohol and drugs.
Sgt. Borja explains that no arrest was made because the incident didn't occur in front of an officer.
Lohan, 24, has been at the Rancho Mirage, Calif., facility since Sept. 28, and was ordered by a Beverly Hills judge to remain there until at least Jan. 3.
It remains to be seen whether the incident would be deemed a violation of Lohan's probation terms stemming from her ongoing DUI case. A violation could send her back to jail.
As of Tuesday, Beverly Hills Superior Court Judge Elden Fox, who's overseeing her case, has not been notified, according to a court source.