Written by the Speaker of the Legislative Assembly Shelley Hancock and President of the Legislative Council John Ajaka, it outlined the pair's view on introducing a new level of scrutiny over the activities of our state's politicians.

Since the Independent Commission Against Corruption first suggested it be considered in 2013 after its investigations into former Labor ministers Eddie Obeid and Ian Macdonald, various committees have been mulling the creation of what is called a parliamentary investigator.

The idea is that, rather than having ICAC investigate every political indiscretion, it should be freed up to focus on major alleged wrongdoing. The issue has gained extra relevance now ICAC's powers have been redefined to investigation of serious, systemic corruption after its failed pursuit of deputy Crown prosecutor Margaret Cunneen.

Issues such as rorting of travel and other expenses, for example, would be left to a new body handed responsibility for investigation, reporting and oversight.

It could be powerful, possibly with the ability to fine MPs found to have acted improperly, demand documents, conduct investigations, publish reports and, if deemed serious enough, refer matters to other agencies like ICAC and the police.

But all of that very much depends on which, if any, model is adopted. And if the recommendations of their respective inquiries are any guide, the two houses of Parliament are far from being in agreement.

In 2014, a parliamentary inquiry by the upper house privileges committee recommended the establishment of a commissioner for standards in NSW, modelled on a position introduced in the British Parliament and the ACT Legislative Assembly.

The commissioner would have the power to investigate matters, impose penalties and make findings public.

The same year, the lower house ethics and privileges committee recommended the establishment of an ethics commissioner, an apparently far less powerful body that would have the discretion to keep investigations and findings confidential.

In 2016, then upper house president Don Harwin began researching a potential model, a task continued by his successor Ajaka, culminating in the delivery of the letter to Berejiklian a few weeks ago.

So, what does their letter say? Interestingly - perhaps tellingly - we are not being told. A request by Fairfax Media for the Premier to release the letter was rejected.

Ajaka says: "Madam Speaker and I investigated the issue thoroughly. We obtained advice in relation to jurisdictional matters and forwarded our report to the Premier for more consideration."

The problem for Berejiklian is that it is far from clear whether or not Ajaka and Hancock agree.

The jurisdictional issues, in particular, are likely to cause complications. For example, if a commissioner for standards is handed the power to fine miscreant MPs, does that interfere with the rights of Parliament?

A further complicating factor may be linked to the need for legislation to establish the new body. No law can take power away from Parliament.

Introducing a new watchdog with the power to investigate MPs can be seen as undermining the existing mechanism whereby matters are referred to the respective privileges committees of the upper and lower house.

It's a complex issue, and one Berejiklian is unlikely to welcome just as she's turning her focus to fighting the March 2019 election next year.

For one thing, many of her MPs won't welcome a new policeman on the parliamentary beat.

There are already fears that referrals to such a new body can be used as a political weapon, much like referrals to ICAC.

Further complicating matters is that the government is already under fire over funding cuts to ICAC.

The opposition has suggested the reason is to pay back the agency's investigation into Liberal Party rorting of political donations before the 2011 election.

Failing to act on advice to establish a parliamentary investigator can easily be exploited - fairly or not - as further evidence of the government's attempts to dodge scrutiny.

Over to you, Premier.

Sean NIcholls is state political editor.