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The Investigative Process

The Office of Investigations

The OIG's Office of Investigations is comprised of criminal and general investigators that are responsible for conducting criminal, civil, and administrative investigations of fraud and a variety of other allegations affecting DOT, its operating administrations, programs, and grantees (grant funds). The Office of Investigation’s top priorities involve crimes with a public safety impact, procurement and grant fraud schemes that significantly impact DOT funds, consumer and workforce fraud, and employee integrity violations. Learn more about OIG's investigative priorities and common fraud schemes. The Office of Investigations also manages a Hotline Complaint Center and investigates whistleblower complaints, including those referred by the U.S. Office of Special Counsel.

The Investigative Process

Allegations Received

Allegations of fraud, waste, abuse, and other irregularities concerning DOT programs and operations are received from various sources, including:

  • Hotline complaints from DOT employees, grantees, contractors and members of the public via website, phone, email, and fax.
  • Referrals from Government entities, including other law enforcement agencies, Congress, the U.S. Office of Special Counsel, the Government Accountability Office, and DOT officials.
  • Internal OIG audit referrals, investigative analyses, and other compelling sources.
  • Qui Tam lawsuits referred for investigation by the Department of Justice.

Preliminary Review

Allegations are preliminarily reviewed to determine if OIG investigative attention is warranted.

  • Is the matter within DOT’s jurisdiction?
  • Is the allegation credible (for example, reasonably detailed)?
  • Would the allegation constitute a violation?
  • What is the best way to address it? Through OIG criminal, civil, or administrative investigation; or referral to an Operating Administration (OA) or other Government agency?

Investigative Activity

Investigations are conducted through a variety of activities, including record reviews and document analysis; witness and subject interviews; IG and grand jury subpoenas; search warrants; special techniques, such as consensual monitoring and undercover operations; and coordination with other law enforcement agencies, such as the FBI, as appropriate.

Investigative Outputs

Upon completing an investigation, reports and other documents may be written for use by senior decision makers and other stakeholders, including prosecuting attorneys and DOT management.

  • Results of OIG’s administrative investigations, such as employee and program integrity cases, are transmitted to OA officials for appropriate action.
  • OIG’s criminal cases are prosecuted through U.S. Attorney Offices nationwide, as well as U.S. Department of Justice prosecutorial elements in Washington, DC. Criminal cases can also be prosecuted by State and other local jurisdictions.
  • OIG monitors the results of those investigations conducted by OAs based on our referrals to ensure allegations are sufficiently addressed.
  • Matters may be referred to OAs for suspension or debarment decisions.