The Broadcasting Standards Authority has declined a complaint about the portrayal of a character with bipolar disorder on the television drama Shortland St.

A storyline about character Jack Hewitt, which screened on the TV2 weeknight series in December and January, upset the Mental Health Foundation and the Bipolar/Manic Depression Society.

During the episodes, Jack Hewitt stopped taking medication after the break-up of his relationship with Rachel McKenna.

He attempted to kill Chris Warner, kidnapped Rachel and committed suicide.

The foundation said the storyline played upon the stereotype that people with mental illness were dangerous and unpredictable.

The society said people with bipolar disorder might, when they became unwell, lose their sense of judgment, but it was uncommon for that to lead to their committing serious crime.

Suicide during mania was quite rare, it said.

Broadcaster TVNZ said Jack Hewitt's transformation from a credible, intelligent and loving person to one who was clearly very ill was presented in a sympathetic form.

At no point did Shortland St imply the behaviour shown was common to people suffering from bipolar disease, it said.

TVNZ said that in story-telling, it was sufficient that the writers established that the erratic behaviour shown by Jack Hewitt was not inconsistent with the reality of a person with bipolar disorder who had failed to take medication.

The authority said that finding a breach of broadcasting standards on this occasion would limit freedom of expression unjustifiably.

Because Shortland St was fictional, standards relating to factual accuracy and those requiring balance, fairness and impartiality were irrelevant, it said.

It also considered that the encouraging of stereotyping did not meet the high threshold required to establish denigration or discrimination.