Cannot enter sleep mode as non-root user (Operation not permitted)

[Jason Hunt]

When attempting to enter sleep mode as a non-root user, I receive the error:

acpiconf: request sleep type (3) failed: Operation not permitted

Searching online yielded a suggestion that the user must be a member of
wheel, however my account is in the wheel and operator groups (confirmed by
running /usr/bin/id)

This is happening on my laptop with a fresh install of 10.3-RELEASE, and
desktop with March snapshot of -CURRENT.  Both systems properly enter and
resume from sleep mode when run as root.

Does anyone have suggestions for how to troubleshoot this?

Thanks

- Jason