David Lammy has discredited questions over whether Angela Rayner owes capital gains tax (CGT) as “smears being run” to distract people from “Tory chaos” and the rising cost of living before the local elections.

The shadow foreign secretary said Rayner had Labour’s full support, that she had done nothing wrong, and that her tax arrangements had been subject to advice from accountants and lawyers.

Lammy’s defence of the deputy Labour leader came after the Mail on Sunday published another story on Rayner’s tax affairs, pointing to social media posts in which Rayner referred to her husband’s house as “home”, while saying her council house was her principal residence.

The newspaper has previously questioned whether she was liable to pay CGT on the sale of her former council house before she became an MP.

Rayner bought her council house on Vicarage Road, Stockport, in January 2007 for £79,000. She was registered on the electoral roll there from 2007 until 2015, was not registered to vote elsewhere and did not rent out the property.

Lammy said the newspaper merely provided evidence that Rayner “had and has a blended family”.

“You meet someone, they have children, a previous arrangement. Many families up and down the country live in more than one home,” he told Sky News’s Sunday Morning with Trevor Phillips programme.

“That’s what the photos I saw reflect and it’s consistent with the advice that Angela took in terms of her tax affairs from accountants and from lawyers. I don’t think this is a story.”

Responding to mounting pressure for Rayner to publish the legal advice she received, Lammy added: “There is a different arrangement in expectation for the prime minister in this context, we’re not yet in government.”

Lammy added: “We all know that there’s an election in May. We know why these smears are being run is to detract from the £870 that average families are less well off in this country as a result of the tax burden. That’s what this is really about. It’s not about blended families … it’s about Tory chaos.”

Rayner paid the council tax and bills for the Vicarage Road property and lived in it before selling it in March 2015, it is understood, all before her election to parliament.

A Labour spokesperson said: “Angela and her husband mutually decided to maintain their existing residences to reflect their family’s circumstances, and they shared childcare responsibilities.

“Angela has always made clear she also spent time at her husband’s property when they had children and got married. She was perfectly entitled to do so.”

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