Mark Reckons asks for Lib Dems' opinions on inheritance tax. Here are mine.
Firstly, as numerous people have pointed out, it seems to be riddled with exemptions and thus quite easy to avoid. The rate is so high at 40% that for people with a lot of wealth to pass on, there's a huge incentive for gaming the system. Indeed, my own parents have given me some money to invest for a house deposit so that it won't be caught up in inheritance tax later (though it's very doubtful that their assets will total enough to even hit the IHT threshold).
A really great argument I read for an inheritance tax was in Redesigning Distribution* - in order to fund a 'stakeholder grant' of the equivalent of a university education for every adult as they turn 18.
However, I think that the boat has sailed on linking IHT to a new good outcome, so it seems to me that the same effect - taxing wealth which is doing little - could be accomplished with a land value tax, which could be rolled up over several years past age 65, say, to be paid on transferral. Of course, that wouldn't tax non-land assets, but the problem with 'wealth', it seems to me, is that it's pretty easy to hide or move to evade taxation.
(* affiliate link -- but this is a really good book if you're interested in basic income and it introduced me to the notion of stakeholder grants)