Federal preemption does not apply in states such as Michigan that have enacted their own statutes providing users more protection than the federal wiretapping laws. (S. Rep.No. 1097, 90th Cong, 2d Session, reprinted in 1968 U.S.C.C.A.N. 2112, 2187). The emerging law is that for cases involving email, state jurisdiction may be exercised when e-mail is intentionally targeted to recipients in a specific state.
The Michigan wiretapping statute requires that all parties to the communication must agree to the monitoring for communication interceptions to be legal. See, e.g.,MCL § 750.539c. There are notable exceptions such as legal surveillance by a state police office or federal official while in the performance of that official's duties, and interception of communication as long at it is done in the ordinary course of business routinely conducted with a valid business purpose at its core. See, e.g., MCL § 750.539g.