Reference:
https://www.ifc.org/wps/wcm/connect/e7e10e94-3cd8-4f4c-b6f8-1e14ea9eff80/45464_IFC_AML_Report.pdf?M

According to the guidance issued by FinCEN and the Federal banking agencies, when a financial institution receives a request for SAR supporting documentation from FinCEN or an appropriate law enforcement or supervisory agency, it must first verify that the requestor is, in fact, a representative of such an agency. This is to ensure the confidentiality and security of the SAR information and to prevent unauthorized disclosures. A financial institution should have procedures for such verification in its BSA/AML compliance program, which may include, for example, independent employment verification with the requestor's field office or face-to-face review of the requestor's credentials.
References:
1: This web page explains the BSA requirement that financial institutions provide SAR supporting documentation in response to requests by FinCEN and appropriate law enforcement or supervisory agencies, and the need to verify the requestor's identity.
2: This document provides answers to frequently asked questions regarding SARs and other AML considerations, including the question of how to handle "keep open" requests from law enforcement.

The board of directors has the ultimate responsibility within a bank for ensuring that the bank has a comprehensive and effective BSA/AML program and oversight framework that is reasonably designed to ensure compliance with applicable regulations. According to the Federal Financial Institutions Examination Council (FFIEC) BSA/AML Examination Manual, the board of directors must approve the BSA/AML compliance program, which includes the BSA/AML policy, internal controls, independent testing, designated BSA/AML compliance officer, and training1. The board of directors must also provide sufficient resources, ensure qualified staff, and hold senior management accountable for implementing and adhering to the BSA
/AML compliance program1.
References:
1: FFIEC BSA/AML Examination Manual, Board of Directors and Senior Management Oversight

Reference: https://www.trulioo.com/blog/enhanced-due-diligence

On-line banking offers a significant money laundering risk to a financial institution because:
The nature of on-line banking can make it difficult to establish who is controlling the account. On-line banking allows customers to access their accounts remotely, without face-to-face contact with the financial institution. This can pose challenges for verifying the identity and legitimacy of the account holder, especially if the account is opened on-line or through a third-party intermediary. On-line banking can also facilitate the use of anonymous or fictitious identities, or the use of proxies or nominees to hide the true beneficial owner of the account.
The ease of access through the internet enables cross border movement of funds. On-line banking allows customers to transfer funds quickly and easily across different jurisdictions, without physical movement of cash or other instruments. This can increase the risk of money laundering, as funds can be moved to or from high-risk countries or regions, or through multiple accounts or financial institutions, to obscure the origin, destination, or purpose of the funds. On-line banking can also enable customers to access or use alternative payment systems or virtual currencies, which may have lower regulatory oversight or transparency standards than traditional banking systems.
The speed of electronic transaction enables execution of multiple complex transactions within short time frame. On-line banking allows customers to conduct transactions in real time, with minimal or no human intervention or verification. This can increase the risk of money laundering, as customers can execute multiple transactions in a short period of time, or use complex transaction structures or patterns, to avoid detection or reporting thresholds, or to conceal the source, nature, or ownership of the funds. On-line banking can also enable customers to use automated or algorithmic trading systems, which may generate large volumes of transactions that are difficult to monitor or analyze.
References:
CAMS Study Guide - 6th Edition, Chapter 5, pages 139-140
CAMS Certification Exam Outline, Domain 2, Task 2.1, Skill 2.1.1
Online Banking and Money Laundering, ACAMS Today, September 2012