The threat of money mule syndicate continues to undermine the stability of financial system. Over the years, money mule syndicate has helped to launder ill-gotten funds by colluding as intermediary. The defense of financial system from ensuing money mule problem lies in the responsibility of financial crime compliance officers. Submission of Suspicious Activity Report (SAR) by these officers helps in combatting money mule phenomenon at the enforcement level. Hence, the building of money mule risk assessment among financial crime compliance officers is unequivocally critical. This paper presents the estimation of reliability of instrument developed to measure the novel money mule risk assessment based on Judgment and Decision Making (JDM) theory. Professional self-awareness, task complexity and AML software astuteness are the constructs influencing financial crime compliance officers’ risk assessment in money mule investigation at bank’s level. An instrument with 118 items was developed and disseminated digitally for pilot test. The distribution of instrument targeted financial crime compliance officers working for financial institutions in Malaysia. A total of 31 respondents from commercial banks in Malaysia participated in the pilot test. The four constructs score Cronbach’s values above 0.80 which show good and satisfactory reliability for the next phase of data collection.