"It’s true that MPs’ total incomes, while often significantly more than the average Brit, are just a drop in the ocean compared to major corporations. But MPs are also the ones who set British tax policy, and they have a say in worldwide tax policy. For instance, in January 2016, the Observer revealed that Tory MEPs were lobbying the EU to protect Google’s £30bn tax haven island. The Mirror discovered that 12 top Tory donors were being investigated by HMRC for taking advantage of tax avoidance schemes. It’s clear that there is an overlap here between what benefits the Tories directly and what the rules are in terms of tax avoidance. That’s why we need total transparency for all MPs when it comes to their taxes.
MPs are elected by us to decide how to spend the taxes we pay. Our taxes for pay their salaries, their expenses, their staff, and their homes. They are in the unique position of being paid public money while also deciding how it is spent. This means they have a responsibility to be as transparent as they can with the British people, so that we can hold them to account. We shouldn’t be asking ourselves why Corbyn has published his tax return; we should be asking why Philip Hammond won’t publish his."
Guardian.