Workplace bullying is putting an enormous pressure on the country's mental health system.

Culture Safe NZ, who help hundreds of victims a year, say some of whom are driven to the brink of suicide because of bullying.

It comes as a fifth of all lawyers who responded to a Law Society survey say they've been sexually harassed and half say they've been bullied.

Director Allan Halse believes each year it pushes thousands of otherwise healthy people into the mental health system.

"People that are going about their normal work, who, after being bullied for a period of time end up at their doctors, they end up off work on sick leave, on medication for depression."

He believes we need tougher penalties for workplace harassment saying Melbourne has a team of 30 at WorkSafe Victoria, dedicated to investigating and prosecuting bullies.

"They've also got Brodie's Law where the bully can actually be prosecuted and they do prosecute and imprison people for causing serious harm or death through bullying."

There is a maximum 10-year sentence under 'Brodie's Law', which was established after 19-year-old Brodie Panlock threw herself off a carpark building after prolonged workplace bullying.