I feel this kind of blackmail should result in the ban of the account of the offender, regardless of whether the offender is a newbie or not, any user blackmailing, or trying to blackmail another user on this forum shouldn't be allowed to stay.
Afaik, abusing the trust system is not a bannable offense. So, despite how annoying this behavior could be, he is unlikely to get banned.
However, the trust system is designed to be as decentralized as possible which makes it the responsibility of the community to make sure it works properly. The best/right thing the community can do is to distrust (~) abusers to make sure they never make it to DT. This way their feedbacks will have no weight.