I am posting this on the criminal forum even though it deals with a juvenile--

We have a juvenile charged with burglary. Neither he, nor any of his family, are here legally. His sister has already been deported.

My question is, do I, as a prosecutor, have a duty to report this kid and his family to INS if I know that they are illegal?

Isn't that the responsibility of the arresting agency?

i report every time

Who should it be reported to? Is there a website that discusses when/how these should be reported?

Call the nearest office of the Border Patrol and ask for an agent. Give the agent the identifiers you have for the person and they will check it out. If they can identify the perrson as illegal, the will place a detainer on him.