The pmpolicy command can be run on policy servers to compare different checked in revisions of your policy, or it can be used to compare a checked out copy that you have modified with a version in the repository. Here is the documentation on using the diff command from the pmpolicy man page.
/opt/quest/sbin/pmpolicy diff [-o outfile] [-c] [-f] [-d dir] [-p path] [-r revision]
/opt/quest/sbin/pmpolicy diff [-o outfile] [-c] [-f] -r revision[:revision]
Check the differences between two revisions of the policy, and
dump the output to stdout, or to the selected output file. By
default, this option displays the differences between the two
selected revisions. If the -f option is also specified, it
displays the incremental differences between each revision in
the specified range. Revisions can be specified using any
acceptable svn revision format (e.g. HEAD, COMMITTED, or DATE
format). The -o option can be used to dump the `diff' output to
a file, rather than to stdout (the default).
· If a directory is specified (and optionally a path in the
directory), it compares the copy in that directory with the
selected revision (or the latest revision in the repository
if no revision is specified).
· If one revision is specified, it reports the difference
between the latest and the selected revision.
· If two revisions are specified, it reports the difference
between the two selected revisions.
When this option is specified, the exit status is the same as
the `diff' utility:
0 no differences were detected.
1 differences were detected
2 An error occurred
# pmpolicy diff -d /tmp -o /tmp/diffs.txt -r2 -c
# pmpolicy diff -r1:2 -c -o /tmp/diffs.txt