On Fri, Apr 7, 2017 at 6:52 PM, Tom Harding via bitcoin-dev
<bitcoin-dev@lists.linuxfoundation.org> wrote:
> A network in which many nodes maintain a transaction index also enables a
> class of light node applications that ask peers to prove existence and
> spentness of TXO's.

Only with the additional commitment structure such as those proposed
by Peter Todd in his stxo/txo commitment designs, e.g.
https://petertodd.org/2016/delayed-txo-commitments