The account officer has violated the principle of confidentiality by informing the customer about the legal request from law enforcement. This could amount to tipping off, which is a criminal offense in many jurisdictions. Tipping off could jeopardize the investigation, compromise evidence, and alert other potential suspects. The account officer should not discuss any details of the investigation with the customer, nor should he meet with the customer to do so. He should also report his actions to his manager and compliance department, and cooperate with law enforcement as required.
References:
* ACAMS CAMS Certification Video Training Course1, Module 4: Conducting or Supporting the Investigation, Lesson 4.3: Confidentiality and Information Sharing
* ACAMS CAMS Certification Study Guide2, Chapter 4: Conducting or Supporting the Investigation, Section 4.3: Confidentiality and Information Sharing, pp. 135-136
* ACAMS CAMS Certification Exam Outline3, Domain 4: Conducting or Supporting the Investigation, Task 4.3: Maintain confidentiality of the investigation, p. 18