BBCNI’s Spotlight programme tackles the issue of public money tonight. The focus will be on the money politicians get for renting and running their constituency offices.

I have little knowledge of the content, although I may make a fleeting appearance on the programme – talking about a case I previously reported on.

But aside from individual controversies over particular claims, there’s a wider issue about MLA office expenses that is worth considering. Does the taxpayer-funded system hand an unfair advantage to sitting MLAs and their parties – in the process helping to copper-fasten the political status quo?

The money involved is not insignificant. MLAs can each claim up to around £70,000 a year under the Office Cost Expenditure set-up. This funds advice centres and satellite offices in their constituencies. These operations are not just about helping pensioners fill in complicated benefit forms.

They can also act as de-facto promotional stations, trumpeting the MLAs and the work they do. They’re also a physical presence in towns, helping to maintain profile, the lifeblood of any political career.

Come election time and incumbent members are not shy about boasting about all the people their advice centres have helped. Having full-time staff based in constituency offices is clearly a big help to any political cause.

And if MLAs are renting their offices from their parties, or bodies linked to their parties, that’s another advantage banked.

The general issue of potential party political advantage from office expenses has been raised in high places.

In its 2009 review of the MP expenses scandal, the Committee for Standards in Public Life said:

“Many staff employed by MPs are also politically active in their own right and a significant number of constituency offices are rented from or shared with local political parties. There must, therefore, be a risk that resources intended to support an MP in their constituency role will deliberately or inadvertently be put to party political use instead.”

In a 2012 report, the Independent Financial Review Panel which sets MLA pay and allowances registered some concerns about the Assembly’s OCE system.

These included “the effectiveness of some of the controls on expenditure and the measures needed to ensure that OCE is used to assist Members in the Assembly only and not for wider party political purposes”.

There is no simple answer to such questions. There is no easy dividing line between constituency work and party political interests. Fighting to get benefits for pensioners is laudable – it also does no harm to re-election prospects.

There’s a clear argument for providing some public funding for the work of MLAs. Politics should not be the preserve of those rich enough to afford it. So it’s down to the messy business of finding the right balance and setting the right controls over spending.

I’m sure I’ll not be the only one watching Spotlight tonight with interest.

David Gordon works for the BBC. In a past life, he reported obsessively on MLA expenses for the Belfast Telegraph. He is also the author of the 2009 book, The Fall of the House of Paisley.