q1 As it says in the Adam Smith paper, income tax, or a "sin tax". I like the following two paragraphs.
If the Exchequer needs money, a conventional approach would be to tax a negative externality. £1.4bn equates to a 3% increase on existing alcohol expenditure, including duty and VAT, of £47bn. Alternatively, if the tax is considered to be a proxy for “taxing the rich”, it would be simpler, less harmful and more effective to “tax the rich”, operating within much smaller margins of extremely well-researched tax levers with existing collection and enforcement mechanisms. £1.4bn is 0.32% of the UK’s £440bn income tax and NIC bill and could be targeted to suit distribution objectives, including contributions from affluent families tending to find the best of state education, if that is indeed the aim. Taxes such as these offer more certain revenue, fewer distortions and fewer avoidance opportunities. Both have the advantage of being well understood by the Treasury and use existing HMRC mechanisms, and are very broadly-based.
Wishing to raise money, few economists would instinctively recommend (1) a new tax offering (2) highly uncertain net revenue potential (3) on a positive externality, that (4) distorts competition and (5) disrupts the education of (in the IFS’ optimistic scenario) some tens of thousands of children, (6) shifting their demand onto a state-obligated supplier; that (7) poses hard-to-quantify risks to the labour supply, value creation and taxes of higher earners, and that (8) requires new legislation, presenting many avoidance opportunities and enforcement challenges and (9) has only one international precedent, said to have caused “general mayhem”.
q2 private schools are and should remain exempt because they deliver education, all of education is exempt from VAT because schools and other providers have social benefit and save ££££s for taxpayers. Part 1 of the above paper lays it out in good detail. And please, just stop saying "subsidised fees". I know it's Labour Party rhetoric but that doesn't mean it's correct. And it's not correct.
The financial crisis is irrelevant. Due to quantitative easing there was little effect on anyone's finances and virtually none on higher earners / asset holders. And, before you ask, I (as an economist) was and remain opposed to quantitative easing and bank bailouts. There's a good subject for you and I to agree on if you're opposed to privilege and the special interests of "the rich".