NSW woman Sara Connor, 45, faces up to 15 years in jail if convicted, after murder charges were laid over the death of a Balinese police officer.
She is also facing charges of group assault and assault causing death.
Erwin Siregar, who is the lawyer of the Byron Bay woman, says she signed a document allowing her detainment for 20 days while the investigations continue.
Police could extend this period to up to 100 days.

David Taylor, Ms Connor's British boyfriend, has also been named as a suspect in the alleged murder of a local officer that was found dead on a beach in Kuta on August 17.
The family of an Australian woman says the allegations she's facing are totally out of character.
"The accusations laid against her are totally out of character for this beautiful person. Her love for her boys is the biggest love in her life. She is very passionate about life and exudes enthusiasm wherever she goes," Ms Connor's Byron Bay family has said in a statement.

