Established in 1986 by the then Director of CID through a letter Ref. CID/PUB/5/6/1/164, Legal and Crime Affairs (LCA) was originally called Analysis and Data Center. Its role then was to advise on criminal cases and Matters that have legal connotations. Later in 2000 during the CID restructuring, the unit adopted its current name Legal and Crime Affairs a name it has since maintained. 
Currently, the office is fully fledged and is composed of Advocates of the High Court of Kenya. These Advocates provide high-quality, timely, and comprehensive advice to the Director, other Directorate officials, Division, and field offices on all aspects of the law. Particularly, the advice touches on the areas of Criminal Law, Public International Law, Extradition and Mutual Legal Assistance, Procurement, and Contract Law, Criminal Investigative Law, Maritime and Admirably Law, Information Law, and Policy matters, all in accordance with the will and the spirit of the Constitution. The Unit also advises on investigations and prosecution involving the Directorate of Criminal Investigations is involved.
In addition to providing legal advice to the Directorate and its departments, LCA reviews the legal sufficiency of evidence, assists in legal drafting particularly replying to affidavits, plaints and petitions, ensures that preferred criminal charges are in accordance with the requisite laws, and supports the office of the Director of Public Prosecution (ODPP) in the criminal prosecution process. 
Additionally, the LCA is the liaison office of the Directorate with the office of the Attorney General (AG) and Director of Public Prosecution (DPP). This is to ensure coordination in the defence of the Directorate and its employees in civil actions which arise out of the Directorate’s investigative mandate and human resource or employment matters.  LCA also provides training support for the directorate on legal issues to National Police Service-DCI Academy, and other Law enforcement training institutions.

Routine Duties

• To provide legal assistance on all matters relating to law enforcement and crime initiatives.
• To peruse case files, inquiry files from all over the country for sufficiency of evidence and provision of legal opinions to investigators.
• To provide legal advice on case management in order to avoid unnecessary complaints against the Directorate and lawsuits
• To liaise between the Directorate, the State Law Office, and the Director of Public Prosecutions.
• To advise the director and staff on matters of Law, emerging legislations, court decision best practices, and policies.

SECTIONS WITHIN THE UNIT

Compliance and Administration Division

Provides advice to the Directorate concerning human resource and employment-related administrative hearings and officers' disciplinary tribunal procedures. Provides legal, and policy advice and guidance concerning criminal investigations, jurisdiction, and operations techniques.

Litigation Division 

In liaison with AG/ODPP coordinates responses to the defence of civil suits filed against the Directorate. Provision of litigation support to the directorate and staff. The section is also responsible for locating, reviewing, and processing the release of evidential materials that are relevant to the investigation and prosecution of criminal cases.

Evidence Evaluation and Analysis Division (EEC)

Peruse and advises on all inquest files, inquiry files, general investigation files, and complaints against staff of the Directorate files. 

Mutual Legal Assistance Division (MLA)

The Directorate is a Competent Authority under the Mutual Legal Assitance Act, consequently LCA acts as the focal point and a coordinator of MLA involving the DCI and other foreign law enforcement agencies. Particularly, LCA drafts the MLA requests, responds to MLA requests from other jurisdictions, and participates in the drafting of bilateral and multilateral MLA agreements with other countries. LCA also liaises with the AG which is the Central Agency on MLA in Kenya for purposes of coordination and implementation of MLA.

Policy Division

The policy division participates in drafting, and reviewing existing national policies that touch on the Directorate and national security in Kenya. The Division also plays a key role in steering legal reforms and amendments touching on the Directorate's mandate and operations, particularly on law enforcement and emerging crimes.