Voting Age in the UK - Lords reject call for 16 year olds to vote in EU referendum

Like many other countries, the UK Government's legitimacy comes from a transparent democratic process which is highly inclusive of its entire population. Part of this legitimacy comes from the age at which individuals are allowed to actually vote - in the UK this is set at 18. Yesterday, the House of Lords voting down an amendment brought by Labour and Liberal Democrat Peers to reduce this age to 16 when the referendum on EU membership eventually takes place (probably in 2017).

The proposal is not without precedent, of course, as the age of 16 was the minimum age set for the Scottish Independence referendum in 2014. It should also be noted that, whilst 18 is the most popular age set for voting, EU members Austria and Malta allow 16 year olds to vote in some or all of their elections. The Isle of Man, Guernsey and Jersey also allow this age group to vote. Even some US states will allow 17 year olds to vote in up-coming primaries if they will be 18 by the time of the Presidential election (2016).

So what are the arguments for and against dropping the minimum age allowed to vote to 16?