Deearnah was born and raised in Perth's southern suburbs. Deearnah was admitted to the Supreme Court of Western Australia in 2018 after completing a Bachelor of Laws, Bachelor of Criminology and a Graduate Diploma of Legal Practice.

During her studies, Deearnah commenced work experience under the supervision of Criminal Defence Barristers. During this practical training Deearnah developed a strong interest for criminal law. Since practicing law, Deearnah has worked exclusively in the criminal defence sphere and has developed a passion for court advocacy and helping people who have been accused of criminal offences to access justice.

Outside of the law, Deearnah enjoys spending time outdoors. Her hobbies include camping, boating, going on bush walks and spending time with family and friends. Deearnah is also a committee member on two law committees and enjoys developing strategies and policies to address issues within the legal community.