A hung jury has led to a mistrial in a case involving a convicted sex offender. The jury in the santa cruz county court case could not reach a unanimous decision on whether or not the defendant should remain involuntarily committed to a state mental hospital. 42-year-old Robert peter clark was convicted of multiple incidents of violent sex acts against children in the 1980s. clark was most recently arrested in santa cruz county in 1998, for being under the influence of drugs and failing to register as a sex offender. His attorney’s argued that he should not be kept in the mental facility because the recent arrests did not involve sex crimes. Prosecutors must now decide whether to re-try the case.