American Bar Association, Standards for Criminal Justice, Standard 4-4.1:

It is the duty of the lawyer to conduct a prompt investigation of the circumstances of the case and to explore all avenues leading to facts relevant to the merits of the case and the penalty in the event of conviction. The investigation should always include efforts to secure information in the possession of the prosecution and law enforcement authorities. The duty to investigate exists regardless of the accused's admissions or statements to the lawyer of facts constituting guilt or the accused's stated desire to plead guilty.

American Bar Association, Standards for Criminal Justice, Standard 5-1.4, supra, p. 47.

National Advisory Commission on Criminal Justice Standards and Goals, Task Force on Courts, 1973, Standard 13.14:
Public defender offices should have adequate supportive services, including secretarial, investigation, and social work assistance.

In rural areas (and other areas where necessary), units of local government should combine to establish regional defenders' offices that will serve a sufficient population and caseload to justify a supporting organization that meets the requirements of this standard.

The budget of a public defender for operational expenses other than the costs of personnel should be substantially equivalent to, and certainly not less than, that provided for other components of the justice system with whom the public defender must interact, such as the courts, prosecution, the private bar, and the police. The budget should include:
1. Sufficient funds to provide quarters, facilities, copying equipment, and communications comparable to those available to private counsel handling a comparable law practice.
2. Funds to provide tape recording, photographic and other investigative equipment of a sufficient quantity, and versatility to permit preservation of evidence under all circumstances.
3. Funds for the employment of experts and specialists, such as psychiatrists, forensic pathologists, and other scientific experts in all cases in which they may be of assistance to the defense.

National Legal Aid and Defender Association, Standards for Defender Services, Standard IV-3:
Essential to the provision of effective representation is the adequacy of supportive services for the defender. Supportive services should include, but are not limited to, secretarial, investigative and other necessary personnel, and sufficient funds should be provided to retain various experts for investigation, consultation, and/or attendance in court.

National Legal Aid and Defender Association, Guidelines for Negotiating and Awarding Indigent Legal Defense Contracts, 1983 Draft, Standard III-8, Investigators:
The contract should specify that adequate investigation services necessary to provide competent representation shall be available to the Contractor. No contract clause should interfere with the contracting attorney's selection, supervision, or direction of investigators.

Seattle-King County Bar Association Indigent Defense Services Task Force, Guidelines for Accreditation of Defender Agencies, 1982, Guideline Number 8:
Public defender agencies should employ investigators with criminal investigation training and experience. A minimum of one investigator should be employed for every three attorneys defending felony cases; one investigator for every four attorneys defending juvenile cases; and one investigator for every five attorneys defending misdemeanor cases.
1. Criminal investigation is an essential element of criminal defense. Offices lacking adequate investigative staff tend to neglect the investigative function and rely on the state's version of witness statements and other evidence. It is not cost-effective for lawyers to do all of the investigation connected with a case. Moreover, where lawyers conduct such investigations, it may be necessary to have an investigator along to refute charges of impropriety and to have a witness who can testify at trial if necessary. N.L.A.D.A., Guidelines for Legal Defense Systems in the United States, 340-41, 1976.
2. Since investigation increasingly is becoming a professional skill requiring professional expertise, investigators should be hired who have the professional skills required. At a minimum, agency investigators should:
   1. Communicate well orally and in writing, and
   2. Be knowledgeable about police practices and procedures and jail practices and procedures, and
   3. Be skilled at interviewing witnesses, and
   4. Be able photographers, and
   5. Understand generally medical records and reports.
3. The agency should ensure that its investigators receive ongoing training adequate to keep them abreast of current techniques in the field.
4. In order to ensure that investigations are conducted in every case where there is a factual question not subject to objective determination, an adequate attorney-investigator ratio is necessary. At least one investigator should be employed for every three staff-attorneys defending felony cases; one investigator for every four attorneys defending juvenile cases; and one investigator for every five attorneys defending misdemeanors.