When he retires, Mr Slipper can expect to receive a yearly pension of about $157,000 for the rest of his life.

However, if he is found guilty of the alleged fraud, Mr Slipper is likely to lose everything besides a refund of his superannuation contributions (without interest).

Mr Slipper's retirement package is especially lucrative because of his long service - 23 years as an MP - and his occupation of highly paid roles including Speaker of the House of Representatives, where he earned an annual salary of $371,463.

The threat to his entitlements provides an incentive for him to resign before he faces court next month, if he fears a guilty verdict and wants to protect his pension.

There is little precedent for Mr Slipper's predicament but legal experts and public servants familiar with politicians' entitlements said an early resignation would likely protect his lucrative pension package in the event of a later conviction, although they could provide no guarantee.

Either way, if he remains in Parliament and is convicted, he will lose much of his entitlements regardless of how severe any sentence is.

Mr Slipper has been accused of using a taxpayer-funded hire car to tour half a dozen of Canberra's finest wineries.

The summons document, released on Tuesday by the ACT Magistrates Court, alleges that on three occasions in 2010, Mr Slipper took a hire car to visit wineries that include the top-rated Clonakilla winery, well-known for its $100-a-bottle shiraz viognier.

The trips described in the document - including journeys within Canberra - cost $1194.

The documents suggest Mr Slipper holds a particular fondness for Poachers Pantry, well known for its gourmet smoked meats.

Mr Slipper has not responded to calls and emails.

However, he has described earlier accusations of Cabcharge fraud as a ''complete fabrication''.

He is believed to be employing Brisbane lawyer Peter Russo, who defended Indian doctor Mohamed Haneef when he was wrongly accused by the Commonwealth of assisting a terrorist organisation.

If convicted, Mr Slipper will have to resign as an MP because the offence is ''punishable under the law of the Commonwealth … by imprisonment for one year or longer'', according to section 44 of the constitution.

The former Speaker faces a maximum penalty of five years' imprisonment.

But even if he were sentenced to less than a year in prison, he would still be forced to resign because his alleged offence carries a maximum sentence of longer than one year, said Anne Twomey, a constitutional law expert at the University of Sydney.

If Mr Slipper is forced to resign because of a conviction, the constitution says he is entitled to ''a refund of his [superannuation] contributions, but to no other benefit''.

Former MPs are also subject to the Crimes (Superannuation Benefits) Act 1989, which addresses the forfeiture of benefits if MPs are convicted of corruption offences.

Leaving aside his retirement package, Mr Slipper is likely to be losing hundreds of thousands of dollars in legal fees.