Key Points:

A man whose brutal bashing of pensioner Nan Withers prompted a nationwide demand for tougher sentences is back behind bars after proving he has not changed his ways.

Harry Goulding Houkamau, 36, was one of three men working for a security firm who were jailed yesterday for standover tactics including threats and armed robbery.

Their home invasion to collect a debt terrified two residents who had $4000 of property taken, and were told they could be shot and dumped in a river.

The heaviest jail term of seven years was reserved for Houkamau, who was previously jailed for 10 years when he infamously robbed a Christchurch menswear store and bashed Mrs Withers with a jack handle in 1997. She suffered a fractured skull and needed 75 stitches in her face and head.

The frenzied attack prompted a citizen-initiated referendum, led by Mrs Withers' son Norm, calling for harsher sentences.

Mr Withers gathered 380,000 signatures to force the referendum, and when it was held in 1999, 91.8 per cent of voters supported reforms to impose minimum sentences and hard labour for all serious violent offences.

Mr Withers, now Christchurch's Deputy Mayor, told the Weekend Herald Houkamau had shown he was still the same manwho "dealt to my mum while on parole".

"I would have loved and hoped that he would see the light ... and pull his bloody socks up. But I have always said that leopards don't change their spots, and sadly they usually don't."

Mr Withers felt that despite the referendum "I have to be completely honest, and say it hasn't changed much".

"I'm very disappointed when I see all these politicians who mean well, but then don't put their hands up."

Houkamau's co-offenders, Shane Michael Ford Wakefield, 23, and Charles Bruce Wharekawa, 29, were both sentenced in the Christchurch District Court yesterday to five-year jail terms.

Crown prosecutor Anne MacGoughan said the three had gone to the house to recover money owed by one of the occupants to Wakefield for repairs after a motor accident. Some irregular payments had already been collected.

Judge John Cadenhead said: "I take a serious view of this offending. People should realise they can't go into other people's homes and intimidate them in the way you have done."