But don't expect it to even slap the wrist of Belinda Neal, the Labor MP whose actions it is to investigate.

For a start, the investigation does not touch on the excitements of Neal's night out at Iguanas Bar on the Central Coast with her husband, John Della Bosca, the stood-down NSW Minister for Education.

It is looking at the words exchanged between Neal and Liberal MP Sophie Mirabella in the main committee of the House of Representatives on May 28.

Parliament's bible, House of Representatives Practice, lists a host of privilege cases, from both Australia and the mother parliament at Westminster.

It might shock some to learn that the celebrated Profumo case, involving a minister, a model and national security secrets, might be the most analogous to the Neal matter.

Both deal with misleading the House, but are at opposite ends of the spectrum.

Making a deliberately misleading statement can be treated as a contempt of Parliament. In Profumo's case, a personal statement containing words which were later admitted not to be true, were found by the House of Commons to constitute a ''grave contempt''.

John Profumo resigned from the House.

Neal denied saying words (''Evil thoughts will turn your baby into a demon'') that were picked up by the parliamentary audio system, but were not recorded in Hansard.

Mirabella ensured the words got into Hansard when she sought a withdrawal, but Neal was not having any of that, at least not at 6.30pm on a Wednesday night in the main committee.

''That statement was not made, so I will not withdraw what the Member imagines she heard,'' Neal said. Challenged by Deputy Speaker Anna Burke, she added, ''I did not make the statement that was said to you. You did not hear it correctly.''

When the House of Representatives next convened, at 9am the next day, Neal was the first MP to speak, telling the House of the previous night's ''robust debate'' and noting Mirabella's request for her to withdraw the offending statement.

''I have had time to reflect on the incident and, though the comments were not completely accurate, I do unreservedly withdraw any remarks that may have caused offence to the Member,'' she said. That would have to qualify as being a withdrawal made as soon as possible, which is what the rules require. Practice notes that a withdrawal can be counted as an apology, which is about the harshest recommendation you can expect from the Privileges Committee (remembering that any action can only be taken by the House itself, where the Government of course has the numbers).

One committee member, not wanting to prejudge what he and his colleagues might find, suggested that seeking to force another apology, which the committee could conceivably do, had all the hallmarks of a closed door on an empty stable.

While this all tends to exoneration for Neal, it might end up tripping Mirabella.

Parliamentary audio, and MPs likely to give evidence to the committee, picked up expressions such as ''pathetic man-hater'' and ''feminist Nazis'' being uttered by Mirabella during the main committee exchange with Neal. They have not been withdrawn.

The Practice notes that there have been various claims that Members have deliberately misled the House, but no Speaker has yet accepted such a claim.

Perhaps this was why the Opposition did not give Speaker Harry Jenkins the chance to consider Neal's utterances and denials. Instead, the Coalition rushed straight to its own motion to make a reference to the Privileges Committee, which the Government could simply have crushed with its numbers.

But it did not, preferring instead to amend the reference to include the whole exchange.

Adding to Neal's likely exculpation is the Practice's explanation that ''Action taken by the House to discipline its Members for offensive actions or words in the House may be regarded as based on the concept of privilege, but in practice the offences are dealt with as matters of order (offences and penalties under the Standing Orders) rather than as matters of privilege or contempt.''

The range of penalties is manifestly less under the Standing Orders. Contempt used to be able to lead to expulsion from Parliament, which has been used only once, in 1920, when a Member was expelled for ''seditious and disloyal utterances''.

However, the Hawke government's enactment of the Parliamentary Privileges Act means that neither House can now expel a Member or Senator.

So, the Neal-Mirabella exchange will come before the Privileges Committee, which actually met on the day after the case was referred to it but looked only at reforming its own operation.

It is unlikely to report any time soon, given that it has only one more meeting, next week, before Parliament rises for the long winter break, not returning until the last week in August.

The fact that Mirabella is due to give birth imminently is likely to further delay the committee's considerations.

It is more than likely that the NSW police report on the serious stuff, the Iguanas Bar fracas and its attendant allegations of undue influence, will be in before the committee takes evidence, blowing it right out of the water.

The committee has a lot of very experienced politicians (Alex Somlyay, Petro Georgiou and Wilson Tuckey) in its ranks as well as the man-rated Parliament's best lawyer (Daryl Melham).

Its chairman, however, is new MP Brett Raguse, who won the Queensland seat of Forde for Labor last November.

Practice notes that ''the chair of the committee is normally a backbench Member of considerable parliamentary experience'' and records that a Minister, the ACT's own Kep Enderby, was once its chair, at the same time that his prime minister, Gough Whitlam, sat on the committee himself.

Some on the Coalition side have suggested that Raguse will find himself the recipient of ''guidance'' from the higher echelons of the Government.

But it is more likely that the old heads on the committee will steer their new chairman and their colleagues to a unanimous report.

Privileges Committees do not fracture, by convention and out of respect for the power they hold over the Parliament - and because playing hard partisan games when the stakes are deliberately lifted will only rebound, over time.