Under what circumstance can a subpoena be served by substituted service?

Substituted service of a subpoena is permissible specifically when a party is purposely avoiding service. This approach allows for the legal procedure to continue even when a party does not wish to be served directly, which can aid in ensuring that the legal process is not stalled due to someone's evasion. In the context of legal proceedings, it is important that all parties are given an opportunity to respond and participate, and substituted service serves as a means to achieve that goal when direct contact is not successful.

In contrast, situations where a party is willing to accept service, or when no one is available at the residence do not meet the criteria for substituted service, as those instances do not indicate an intention to evade service but rather provide alternative circumstances. Additionally, the nature of the court—whether federal or state—does not inherently affect the applicability of substituted service for a subpoena; the rules governing service for subpoenas are determined by state laws. Therefore, the primary situation warranting substituted service is indeed when a party actively avoids being served.