My house is on city sewer. Friday, everything backed up due to the city's mainline being stopped (rags, of all things) -- overflow on laundry drain, tub filling, etc. Saturday, when everything was fixed with the city, the same happened. I removed the trap from the furthest drain (laundry) and any water run in the house (shower, toilet, kitchen sink, which is at the very front of house) drains out of it, so I believe the problem is with the line outside the house. City says sewer on our street is flowing fine, but I can find no blockage in the house. I am quite confused.

HeyDeeter,
Did you open up the cleanout to check your sewer line? I have a hunch that when the city main got blocked and crap and crud backed up in the system that a load of it got forced into the city raiser,( where you connect to the city) and your line is clogged there. To check my theory open up the clean out and cycle the washer a few times. Watch the cleanout and if it backs up the problem's at the city raiser or in your sewer line. Good luck, Tom

Problem was at raiser, so the city gets to foot the bill, which makes me happy.
Actually, it makes the wife happy. Thanks for the help.

Jon