As Horn argues, in most cases there is relatively little that parole agents can do to keep an offender who is determined to commit new crimes from committing them.
Parole agents might do a better job if they were paid better. 
mnli hypothesis: Parole agents might do a better job if they were paid better.  premise: As Horn argues, in most cases there is relatively little that parole agents can do to keep an offender who is determined to commit new crimes from committing them.