New Zealand needs to keep its dignity and prove it has its own sovereign justice system in the face of an extradition process to the United States, says the first of the Megaupload accused to make it out of jail.

Computer programmer Bram van der Kolk was arrested last month with three others, including Megaupload founder Kim Dotcom, for an alleged copyright breach worth more than US$500 million ($604.8m).

The case was brought by the US government, and van der Kolk won bail on Thursday.

The men face five charges laid in an indictment by a US grand jury in Virginia, and New Zealand police have faced accusations of being heavy-handed while raiding Dotcom's Auckland property.

Special tactics group and armed offenders officers were used.

Van der Kolk yesterday spoke to the Sunday Star-Times from his Orakei home in Auckland.

"I'm still in love with New Zealand despite everything that has happened," he said.

"I really hope New Zealand will keep its dignity and can show that it is a sovereign state that has its own justice system."

He was "flabbergasted" by the raid and never expected the possibility of an American-led arrest.

Megaupload was established in the United States and had got good legal advice on how to run the business, he said.

"I couldn't believe it. I still can't believe it ... it doesn't matter who the opponent is, if it's the FBI or the American president himself, I'm still very confident we have a very strong case."

If the extradition notice is successful, it will likely be signed off by US Secretary of State Hillary Clinton.

Van der Kolk was released on the same day authorities seized Dotcom's $4.3m Coatesville mansion. Dotcom remains in jail.

New Zealand's role in proceedings had an element of "pandering" to the US, civil liberties lawyer Gary Gotlieb, of Auckland, said.

"I certainly can't imagine doing this for other countries. There seems to be some sort of favourable preference that has gone here.

"There is a huge amount of [New Zealand] resources and manpower in this."

The extradition process would be footed by New Zealand taxpayers.

Gotlieb said people were scratching their heads over the "high-handedness" of authorities in dealing with the case, especially in the seizing of Dotcom's property. The Official Assignee on Thursday confirmed that staff had seized the house along with items, including jet skis, another car and jewellery.

Van der Kolk said three weeks in prison was a new experience as he had never fallen foul of the law before.

He spent some of his jail time talking to other inmates about their lives and encouraging them to get back on the right track.

"We were a little out of the ordinary in prison and it's quite a harsh environment so [Corrections staff] tried to look after us."

As part of his bail conditions, van der Kolk is not permitted access to the internet, but a home phone line allowed him to call his mother. His father had flown from the Netherlands to be with the family.

"I'm tough enough to deal with this situation, but the only thing that is really difficult is being separated from your family."

Though Dotcom's lavish lifestyle has been the subject of much comment, van der Kolk said, "I'm a humble programmer with a wife and two-year-old son". He was always ambitious and had worked hard for the last seven years without leaving much time for himself.

He had seen Megaupload grow from a "small seed, to a small plant, to a tree, to a big kauri".

"So now it is very sad."

- Sunday Star Times