A district attorney has an awful burden on his shoulders.The success or failure of the entire peace agreement will rest on the shoulders of the peace keepers.
on (one's) shoulders
One's own responsibility or obligation. My siblings' care has been on my shoulders ever since our parents died.
*on someone's shoulders
Fig. on someone's own self. (*Typically: be ~; carry something ~; fall ~; have something ~; leave something ~; put something ~.) Why should all the responsibility fall on my shoulders?She carries a tremendous amount of responsibility on her shoulders.