A mother charged with murdering her 4-year-old daughter at their Auckland home will today face an insanity hearing.

The hearing, before the High Court at Auckland, is expected to decide whether Evelyn Kathleen Sen is fit to stand trial.

Sen is charged with murdering Maggie Renee Watson at their home in Onehunga on August 6 last year.

She reportedly called police at 4am and when officers arrived at the Moana Ave home they found Maggie dead.


Sen was treated for what were described as "superficial injuries" and was in mental health care when her daughter's funeral was held.

She was charged with murder in February this year and pleaded not guilty to the alleged offence. The trial was scheduled for November.

Today's hearing is being held under section 20 of the Criminal Procedure (Mentally Impaired Persons) Act 2003.

That section states that before or at a trial a judge must find the defendant not guilty on account of insanity if:
• The defendant indicates he or she intends to raise the defence of insanity; and
• The prosecution agrees the only reasonable verdict is not guilty on account of insanity; and
• The judge is satisfied, on the basis of expert evidence, that the defendant was insane within the meaning of section 23 of the Crimes Act 1961 at the time the offence was committed.

In most New Zealand cases when someone is acquitted of a crime on insanity grounds, the presiding judge orders them detained as a special patient.

They remain detained at a forensic mental health facility until the Minister of Health or National Director of Mental Health deem they are no longer a risk to themselves or others.