Paul Bush of Legal Dockets Online has compiled a list of the courts not using CM/ECF. CM/ECF allows courts to accept filings and provide access to filed documents over the Internet via PACER.
He writes:
Since CM/ECF systems have been successfully implemented throughout the U.S., some researchers incorrectly assume that all case dockets and filings can be located and downloaded using CM/ECF. It’s important to recognize that certain court case information is not presently contained within a CM/ECF database.
Note that the Wisconsin Western District Court is one of the courts listed. I have, however, heard that Western District will connect to the CM/ECF later this year. It will be the last federal district court in the US to do so.