The Conservative MP Douglas Carswell told BBC One's Politics Show that MPs with outside incomes could make better legislators.
Douglas Carswell MPs "beholden to party whips"
He called the current crop of parliamentarians "frankly a parliament of full time hacks".
And he said that banning outside interests makes MPs totally "beholden to party whips":
"If you ban outside interests, you're going to have a parliament of Whips Office patsies. We're almost there. I think we need to change it and we need to make sure that instead of a parliament of Whip's Office patsies, we have a parliament of ordinary citizens who are representative of us in every way."
But Labour MP John Mann, who opposes MPs having second jobs, said:
"Second jobs are cash for access, it's private companies using MPs, it's insider trading of information and contacts."
The Work and Pensions Secretary Yvette Cooper has given an interview with BBC One's Politics Show on the new "national plan" which is expected to be published tomorrow.
"There will be some measures where we are going further and where we are announcing new things, there will be others where we are saying, 'look, this is our priority, and this is something that's very different from what the Conservatives' priority would be'."
She said it would contain new announcements but said she wouldn't pre-empt the content before the document is published to Parliament.
Ms Cooper said targets had helped to drive improvements in a range of public services but that the new strategy was about improving accountability.
"Having made those improvements, the next step we now need is to be able to say, 'okay, those services are now accountable to local people'. Local people should be entitled to things from their health service, from their education service, and that's how we measure improvements in future."
Jon Sopel asked Ms Cooper whether the new document would just end up becoming a "lawyers' charter."
She said the punishments would depend on the service concerned, refusing to comment on whether hospitals would have money taken away if they failed to deliver.
"There are areas in which we do have penalties where actually we don't get the services improved, but this will depend on particular areas. It's not for me to set out the way in which it will work, for example, in a particular hospital - that will be set out by the Health Secretary as we set out further details."
Leader of the Liberal Democrats Nick Clegg also spoke to Jon Sopel live from Glastonbury.
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