Writing in the i newspaper, Jon Trickett, MP for Hemsworth, said Ms Swinson’s opposition to Jeremy Corbyn becoming the leader of a caretaker government showed “to have any chance of electoral success, the Lib Dems need to woo disaffected Tories”.
But he said voting for the Lib Dems would instead usher in a Conservative government.
Mr Trickett, a Labour politician and Shadow Minister for the Cabinet Office, said: “The Lib Dems’ former positioning as equidistant between the two main parties was ditched in 2010 when it jumped into bed with David Cameron’s Conservatives, and supported him through five years of regressive policies and the dismantling of our public services.”
He said the party helped usher through austerity and Ms Swinson herself voted for the bedroom tax and cuts to social security.
“What is more, the Lib Dems seem to be openly taking in any Tory who believes the party’s hardline Brexit stance is no longer attractive to their own constituents, in areas which broadly back Remain – despite their political values and allegiance remaining far to the right of what most people would consider to be centre ground,” he said.
“The Lib Dem strategy therefore requires the party to be both ultra-Remain – hence Swinson’s insistence that she would unilaterally, and undemocratically, revoke Article 50 – and staunchly anti-Corbyn, so it doesn't frighten off potential Tory waverers.”
He added: “A vote for the Liberal Democrats is likely to result in a Tory government.”
If the Lib Dems dispute all this, they can do one simple thing: vote with us to bring down this rotten Tory government and install Jeremy Corbyn as prime minister to prevent a no-deal Brexit and then call a general election.
The Liberal Democrats have been contacted for comment.