Senior SNP MSPs have raised doubts about Scottish Government housing policy during a session on tax rises for second homes.
Kenneth Gibson said he was “not aware” of evidence that the charge helped first time buyers get on the housing ladder.
His colleague Michelle Thomson, who declared an interest as an owner of buy to let property, said she believed there is evidence landlords are starting to leave the market.
Under draft Budget plans, the Government intend to increase the Additional Dwelling Supplement from 4 per cent to 6 per cent.
ADS is paid by people who purchase extra residential properties separate from a main residence.
At Holyrood’s Finance Committee, SNP convener Gibson quizzed Minister Tom Arthur:
“You've talked about supporting first time buyers. Where is the evidence the additional dwelling supplement has actually helped first time buyers and encouraged them into the market?
"Because although it may impact on second homes, I'm not aware of any evidence to suggest it's actually helped increase the number of people that are able to go onto the housing ladder in the first place."
Arthur replied: “So the policy intent is to allow first time buyers to compete more effectively. That is ultimately what the policy intent is.”
Gibson had earlier described as “daft” the fact that local authorities pay ADS, while other registered social landlords do not.
Thomson, who represents Falkirk East for the Nationalists, said she was “not uncomfortable” with the Scottish Government raising revenue through tax, or with the longer trend of a smaller private rented sector.
But she asked: “Do you undertake a risk assessment of tax changes based on setting out the risk, the probability of it occurring, and the impact if it does?”
Arthur said: “We consider what the behavioural impacts are going to be both in revenue and, as I set out with relation to the framework for tax, how it relates to wider objectives as a government.”
She said: “But looking at it from the other side of the fence, there is evidence that landlords are starting to leave the market and that will absolutely have an impact on available supply, and therefore rents.”
She added: "I am very supportive of what the Scottish Government is trying to achieve, but there has to be an assessment of the effects, behavioural effects and so on.
“And thus far, I haven't been convinced there's a recognition of that, and I certainly haven't seen any data that would support that in terms of risk.”
Gibson and Thomson have also raised a series of concerns about the Government’s national care service policy.
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