Those terms were imposed by Judge Stephanie Sautner, who is retiring and will no longer handle Lohan's case.
The crash that prompted the current charges occurred in June on Pacific Coast Highway while Lohan was on the way to a movie shoot.
Terry White, chief deputy city attorney in Santa Monica, declined comment on the letter. He said discussions about a possible resolution are scheduled to take place this week.
Lohan, 26, was on her way to a beach shoot with another person for the TV movie "Liz and Dick" when her car crashed into the back of a dump truck. Police allege she lied about being behind the wheel.
Heller is also seeking dismissal of the charges against Lohan, arguing that police ignored her when she said she didn't want to be interviewed without her attorney present.
Lohan was at the hospital at the time, not in custody, and showed no signs of impairment when officers gave her a field sobriety test, the lawyer said.
Anthony McCartney can be reached at http://twitter.com/mccartneyAP