The return of Ashbygate is not something Malcolm Turnbull should take lightly, and he will need to take a brutally dispassionate look at the actions some of his senior MPs took during the saga, writes Paula Matthewson.

Prime Minister Malcolm Turnbull heads back to Parliament today, refocusing on domestic political issues after a whirlwind overseas tour that took in five nations and meetings with world leaders.

As he canvasses the news of the day, the PM won't be particularly happy to see certain media organisations agitating for greater religious profiling of the 12,000 Syrian refugees being vetted for resettlement in Australia, in the wake of the Paris terror attacks.

Turnbull will be relieved to note the absence of at least one messy political issue from the front pages - an issue that, if handled poorly, could be as damaging for Turnbull as "Choppergate" was for his predecessor.

"Ashbygate" is the highly unoriginal moniker given to the tawdry political saga that involved former staffer James Ashby and his one-time employer, the previous Liberal MP for Fisher and then independent speaker, Peter Slipper.

Ashby revealed, when he laid sexual harassment charges against his former boss, that he'd consulted a number of Liberals about his complaints while still employed by Slipper. This included the former Howard government minister, Mal Brough, who was challenging Slipper at the time for Liberal preselection in Fisher.

Ashby also disclosed in media interviews that he'd had discussions with Queensland Liberal MP Wyatt Roy and the then leader of opposition business, Christopher Pyne.

The discussion with Pyne was particularly pertinent, given Slipper's defection from the Liberal Party helped strengthen the precarious hold PM Julia Gillard had on minority government at the time.

Within this context, Ashby's allegations looked suspicious and politically motivated, and the federal court found accordingly.

There were subsequent legal manoeuvres, with Ashby successfully challenging this ruling, and then dropping the case, while Slipper was separately found guilty, and then successfully overturned the charge, of misusing taxpayer-funded taxi vouchers.

By the time the Abbott government was elected in 2013, many thought Ashbygate to be well and truly over. However, there was no resolution of the questions raised about the role played by Liberal MPs.

In his finding against Ashby's original complaint, the Federal Court judge, Justice Steven Rares, described the case as an abuse of political process. Rares pointed the finger squarely at Brough, concluding that Ashby and fellow staff member Karen Doane had worked with Brough "to cause Mr Slipper as much political and public damage as they could inflict on him".

Brough also admitted in a media interview that he'd asked Ashby to make copies of the then speaker's diary, apparently to prove Slipper's suspected abuse of travel allowances.

It has been a point of considerable speculation since then how Brough's actions avoided any further political or legal scrutiny. After securing preselection for Fisher, he was elected in 2013, but was not returned to the ministry until Turnbull became leader in 2015.

Curiously, out of all the portfolios options available to him, Turnbull made the former assistant treasurer and families and community services minister, his new Special Minister of State. That is, the minister responsible for parliamentarians' entitlements.

So it's unsurprising there have been mutters about the appropriateness of putting an MP with a shadow hanging over his own integrity in charge of the same quality in other MPs.

Those mutters turned to chatter last week when the Australian Federal Police conducted a search of Ashby's home, apparently due to a renewed complaint from Slipper about his diary being illegally procured by Brough. The search warrant reportedly also named Wyatt Roy, now a junior minister in the Turnbull team, as well as Christopher Pyne.

This is a doubly bad development for PM Turnbull. It's not just a bad look to have dodgy-looking ministers in one's handpicked frontbench; it's even more potentially damaging when the very same MPs are one's key lieutenants and supporters, which is the case for Turnbull with Brough, Roy and Pyne.

Conspiracies abound as to why Slipper has chosen now to refresh his charges against Brough, with the net potentially widening to ensnare additional Turnbull ministers. One theory even has former PM Abbott encouraging Slipper to tear down Turnbull supporters in the hope of hobbling the ever-ascendant PM.

John Howard cut a swathe through his ministry to keep good faith with the voting public when it was discovered that some ministers had misused their entitlements. In contrast, Abbott resisted booting speaker Bronwyn Bishop until it was too late, even though her use of entitlements was not in keeping with community expectations.

PM Turnbull will no doubt be looking to find a happy medium between the two responses. He won't want to be unnecessarily punitive, but equally he cannot afford to simply take Brough and co. at their word.

Whatever the reason for its resurgence, the revival of Ashbygate is not something Turnbull should take lightly. The PM needs to take a brutally dispassionate look at the evidence that could be levelled against Brough, Roy and Pyne, and make a clear-headed decision - does the political cost of keeping them outweigh the cost cutting them loose?

Paula Matthewson is a freelance communications adviser and corporate writer. She was media advisor to John Howard in the early 1990s. She tweets and blogs as @Drag0nista.