Lawyers say an independent investigation needs to be undertaken into the 2009 Montara oil spill, which saw millions of litres of light crude strewn across the Timor Sea.

The Australian Lawyers Alliance has backed previous calls for a deeper look into the spill that may have led to the deaths of over a dozen people due to exposure to oil and dispersants.

A statement from the Alliance says the livelihoods of fishing communities have been decimated since the spill too.

The official stance of the Australian Environment Department is that there has been no evidence of deaths as a result of the incident. The Department also said it was still monitoring the environmental impact.

An interim report on the damage in 2012, from authorities at the Centre for Energy and Environmental Studies in Jakarta, found the oil and chemical dispersants used continue to affect marine ecosystems. The chemicals cost coastal communities more than $AU1.5 billion per year in lost earnings.

PTTEP Australasia, the owner of the oil platform which leaked and caught fire four years ago, took several weeks to plug the wellhead as it spewed oil into the ocean. The company has accepted responsibility for the incident.

The Thai government-owned company was fined just over half a million dollars for the massive spill.