I sat once on a boat in the Marlborough Sounds as an elderly Maori man described the history of an obtrusive garish pink house at the head of the bay, metres from the high-water mark.

"He asked me if I would mind if he put up a tent," he said, gazing back into the past, for it was his family land on which the house stood. "Bit by bit, he kept on building things.

"I said to him once: 'That's a pretty funny-looking tent you got there, bro'," he recalled. "He didn't say much."

"So he's squatting, isn't he?" I said. "Why don't you just take legal action against him?"

"No point in that," he said. "Besides, he's a lawyer."

In the "besides" is a clue; the two sentences contain two discrete explanations for what I saw as inaction.

Whether the opportunistic trespasser had been a lawyer or not, the idea of legal action was alien to the old man's idea of what constitutes justice.

His presumptuous neighbour's transgression went far deeper than a breach of the (Pakeha) laws of contract and private property. And no decision of a (Pakeha) court would heal the wound that had been inflicted.

I thought of that old man as I read Barry Barclay's provocative, wise and compelling examination of the collision - or rather the complete lack of intersection - between Maori and English notions of intellectual property and ownership. For here is a book that addresses the way Maori and Pakeha - in matters of law and much more besides - talk past each other.

Barclay has long been one of our most thoughtful filmmakers: his Ngati (the first feature by a Maori director) is the film I recommend to foreigners who want to get a handle on what makes this country tick.

His 1985 documentary The Neglected Miracle was a chillingly prescient study of the erosion of plant genetic diversity in the Third World by seed companies working for first-world profit, and Te Rua in 1991 was a raw and uncompromising drama on the question of ownership and control of indigenous artefacts.

In a sense, then, Barclay's been writing Mana Tuturu all his life and it shows in the meditative, almost tender, and conversational tone.

The subject matter may sound dry but the writer adopts the tone of a fellow chewing the fat over a cup of tea.

That's not to say that he sacrifices intellectual rigour in favour of approachability.

The book bristles with historical and legal references though it has no index (it does have a short bibliography).

In essence Barclay's argument is that "we have in this country a rich indigenous legal tradition [that is] neither extinct nor extinguished".

The Maori word for it is tikanga, from "nga tika" meaning roughly "the right things [to do]". As that name suggests, it is based not on constraining our liberty to do certain things (like build a house on someone else's land) but on underlining the rights that accompany ownership.

In the end, Barclay commends to us the idea of looking to "our" law (the "our" is deliberately inclusive, as the book is). "This is not only the culturally sound way to go," he writes. "I believe it is the only sound way to go legally as well."

This is an important book by a man who has much to say to Maori and Pakeha alike.

We would all do well to consider closely the message that this book contains.

* Published by Auckland University Press $44.95