That might be initially appealing, but it does not take account of a number of factors.
One is the rights of children as written into the Convention on the Rights of the Child which recognises that the ability to form a view and have it heard develops with age. A second one is that it is entirely possible — actually, it is entirely appropriate — to have different ages for different rights and responsibilities. And a third is a specific aspec of that, which is that a right in one domain — our limited form of democractic decision-making — should not be contingent on a responsibility in another — crime, in Eagle’s example.