At least tens of thousands of people think we should, anyway.
A new petition-led campaign to make it so by The Revolution Will Be Televised's Jolyon Rubinstein, who once presented chancellor George Osborne with a GCSE maths book and describes himself as a "Bafta-winning pain in the arse", also has the backing of a number of famous faces - including Russell Brand, Professor Green and Jack Whitehall.
Borrowing a gesture from the Make Poverty History campaign, a video published on the petition website shows celebrities clicking their fingers as a representation of each time a politician lies.
Rubinstein explains on the petition that he does not actually want a law banning lying in Parliament to be passed but rather wants to open a public debate - particularly in light of the current distrust and lack of interest in Westminster politics.
If enough of you sign, it will send a message that we have had enough of broken promises, massaged statistics and the double speak we feel we've been subjected to over the years. Today, less than 1 in 4 people trust MPs. This can't go on.