She said what she had done was "to publish information," and yet she was accused of the 'crime' of committing "an activity detrimental to democracy."
She added that she was unclear as to whether she was accused of "forging false documents" or obtaining documents through "criminal leakages" as she had been accused of both in the past few days.
Rewcastle-Brown said she was not plotting anything and held no vested interests in her reports on 1Malaysia Development Berhad.
Bukit Aman CID director Comm Datuk Seri Mohmad Salleh said in a statement on Tuesday that the arrest warrant issued by a Kuala Lumpur court was for activities detrimental to parliamentary democracy under Section 124B and 124I of the Penal Code.
Section 124I deals with publication of false reports or makes false statements likely to cause public alarm via newspapers, periodicals or other printed publication or electronic means.
Jail term for the offences can be extended to between five and 10 years.