there are no *BSD packages on deb.torproject.org (website states otherwise)
the website  states:
We have packages for Debian, Red Hat, Gentoo, *BSD, etc there too.
but as far as I've seen, the torproject does not offer packages for any BSD OS.
There are packages for debian/ubuntu/fedora/centos but not for FreeBSD, OpenBSD, ...
the sentence should read:
We have packages for Debian, Ubuntu, Fedora and Ret Hat/CentOS there too.