Halden was educated in Western Australia and obtained a Bachelor of Arts degree majoring in Social Work.
Prior to entering parliament he was employed as a social worker and a counsellor for the Family Court of Australia.
Halden represented the Western Australian Branch of the Commonwealth Parliamentary Association at the 22nd Australasian and Pacific Region Conference, New Zealand, September 1991.
In 1992, Halden tabled a petition in the Legislative Council in the initial public act of the scandal which became known as the Easton affair.
He later started a lobbying office, representing clients seeking consideration from the government of Western Australia.