Last Night's Television - Seven Days in Traffic, ITV1; On Expenses, BBC4

We saw the iceberg first in On Expenses, Tony Saint's sprightly drama about the woman who helped lift the lid on parliamentary expenses. Heather Brooke was seen in a dance studio, learning a routine to the song from Fame. Then we cut to the Titanic – Michael Martin playing the bagpipes in his House of Commons office, supremely confident of his unsinkability and unaware that he was already on a collision course. The contrast was pointedly in Brooke's favour – energy and feistiness and youth against age and varnished tradition, and that balance barely wavered in what followed. If you wanted a nuanced and scrupulously fair account of how MPs had become tangled in a corrupt system this wasn't for you. If, on the other hand, you just wanted to laugh at them again, with the help of a mordantly written political farce, it most definitely was. The tone was established by the opening disclaimer: "Some scenes have been imagined, some dates have been compressed. But mostly you couldn't make it up".

That's a serious comment on what happened, not just a scriptwriter's in-joke. Looking back, what was taken for granted for years seems almost fantastical now – that elected officials should react to inquiries about how they were spending our money with a blustering outrage. And the implication of Saint's drama was that it took an outsider to see the absurdity and do something about it. Raised on American expectations of accountability, Heather Brooke first cut her teeth on the intransigence of a local council, pestering relentlessly until the lights were restored in a grim local underpass. Then she set out to bring illumination to a far more critical bit of civic architecture. She was brash, indifferent to tradition and very happy to be a nuisance – virtues encapsulated in a little scene in which she temporarily blocked the Speaker's procession to the chamber. "Hats off, strangers," bellowed a Serjeant at Arms, but she remained defiantly behatted.

The man she was up against – in this characterisation at least – combined shop-floor toughness with an over-inflated sense of his own, and Parliament's, dignity. Martin was played by Brian Cox as a bit of a bully, peremptory with junior staff and fiercely protective of the privileges he'd risen to. "As long as I'm sitting here, members of Parliament will get every ounce of respect that they're due," he growled when Brooke's requests for details of expenses started to become a nuisance. He couldn't see that everything he was doing contributed to their eventual disgrace. Politicians themselves might quibble with some of the spin given to their devices and arrangements here: I doubt that the revised rules on designating what was a "main home" were introduced with quite such knowing, nod-and-a-wink underhandedness. Or that the demands were pressed quite as comically as suggested here. "I can't be expected to live in a house with an Artex ceiling!" wailed one MP, insisting on the legitimacy of a claim for redecoration. But the broad truth of the thing was incontrovertible and Saint's script was full of deadpan comic bounce.

Alex Jennings had a lovely part as the head of the Fees Office, unwillingly pressed into Martin's two-prong defensive strategy against impertinent outsiders. "I really have no experience of being a prong," he said plaintively, shortly before being volunteered for the hopeless task of defending Parliament's position in front of a tribunal. And Saint gave Brooke a nice line when she was suddenly struck by panic before the High Court appeal on which Martin wasted another £100,000 of taxpayers' money. "Now I know what it's like being British," she said, faced by the apparently immoveable inertia of the Establishment. "This is what it feels like all the time... it's awful! How do you stand it?"

You might say the same about rush-hour traffic, a collective insanity that we will surely one day see with a startled bemusement at our own stoical folly. Seven Days in Traffic, ITV1's documentary, sought out some of the individual stories embedded within the 10 million or so car journeys conducted every day in London, cutting from the banal purgatory of the school-run to the kind of journeys that can reasonably be described as life-or-death affairs. A young boy and his grandmother travelled in to separate hospitals in preparation for a kidney transplant. Ambulance men wove through the commuters, given a different perspective on congestion and delay by the job they did. And there were also people for whom the crawling traffic offered a reprieve not an ordeal. In a police van, a remand prisoner asked to move to a cubicle on the passenger's side of the vehicle. "You like to be close to the pavement to look at the totty, don't you?" said the warder knowingly. It isn't the cars that cause the problems, in other words. It's the people inside them raging to be somewhere else instead.