Defendant appealed the decision of the trial judge sustaining the violation of R.I.G.L. 1956 § 31-20-9 (obedience to stop signs).  The Appeals Panel held that it lacked the authority to assess witness credibility or to substitute its judgment for that of the hearing judge concerning the weight of evidence on questions of fact.  Therefore, the Appeals Panel could not substitute its judgment for that of the trial judge and sustained the violation.