On May 5, Justice Simon Moore told Lewis it was "almost inevitable" she would receive a term of imprisonment.
While working for a previous employer, Lewis "developed bonds" with some of her clients, with several considering her to be a close friend.
When she left and set up her own companies, Lewis Administration Limited and Algin Trust Services Limited, several clients moved their trust administration and personal investments with her. All were elderly.
She acted as her clients' agent or as a trustee for her clients' trusts, thereby gaining complete control over their assets.
Ms Read said Lewis then stole from her clients, in some instances using forged documents to commit the offences.
Between 2005 and 2011 she stole approximately $1 million in total, with one victim duped out of $193,669.
Of the money taken, about $830,000 was used for Lewis' personal expenses. Cash withdrawals of about $30,000 cannot be traced.
Justice Moore earlier suppressed the identities of Lewis' victims.