A computer system used to record and hold property titles is insecure and open to abuse, a barrister has warned.

The Law Society has prosecuted a lawyer who had withdrawn a caveat placed on a farm by third parties. The lawyer had no authority to act for the third parties, did not have their consent to withdraw the caveat and did not hold a Landonline Authority and Instruction from the third parties authorising him to withdraw the caveat, the society found.

Rod Thomas, an Auckland barrister and AUT lecturer, said he was worried about the system and the case gave weight to his fears.

But a Law Society spokesman and Robbie Muir, the Registrar-General of Land, said the system was secure.

Muir said cases of fraud were extremely rare.

Property titles were guaranteed by the Crown under the Land Transfer Act 1952.

Land Information New Zealand had robust security measures and systems in place to support this, Muir said.