easy mark

This is necessary for civilization to exist, but it makes humans easy marks when faced with an apparent psychopath.

Not only that, River was selected specifically because he was seen as an easy mark.

Before Abigail’s bloody secret is revealed, ballet is meant to code her as young, innocent, an easy mark.

It appears that Trump is an "equal opportunity disparager," doesn't care about anyone else and is probably disdainful of his base for their being such easy marks for whatever he wants to do.

Spacey was an easy mark for men who hopped on a “bandwagon” and fabricated stories in hopes of a payout, attorney Patrick Gibbs said.