What the theory reaches today
Honest services fraud is a federal prosecution theory built into the mail and wire fraud laws. It treats a scheme to deprive the public or an employer of a person's honest services as fraud even when no one can point to a direct financial loss. For years it was used broadly, including against undisclosed conflicts of interest, but the Supreme Court has narrowed it so that it now reaches bribery and kickback schemes. It is used against public officials and against private employees who owe a duty of loyalty to their employer, and the people who offered the payments can be charged as well. The edges of the theory continue to be argued in court, and prosecutors often bring it alongside other corruption counts.
How an investigation usually surfaces
Many people learn about it through a grand jury subpoena for records, a visit from agents at home, or a letter calling them a subject or target. Sometimes a colleague has already begun cooperating, which is not something you will be told. Agents who arrive unannounced may be friendly and may say they only want your side of the story, but anything you say can be used, and knowingly false statements to a federal agent are a separate crime. You can decline to talk and ask for the prosecutor's contact information. Preserve your records and devices as they are, including personal accounts used for work, and do not reach out to others involved to compare recollections.
First decisions with counsel
Early on, a lawyer usually contacts the prosecutor to learn whether the government sees you as a witness, a subject, or a target. That status shapes everything else, including whether to produce documents voluntarily, whether a proffer makes sense, and whether you need counsel separate from your employer's or agency's. Payments that were disclosed, approved, or part of an ordinary business relationship can look very different once the full record is assembled, and so can gifts that had no link to an official decision. Counsel will want to understand what you have received, who else may be involved, and what your role actually was.