I agree, a black and white Glen Plaid is a terrific look but could be too severe for some industries. My suggestion would be to find a more earth toned Glen Plaid with a subtle window pane. This suit is very acceptable whenever and wherever you go. And don't forget to acquire a chocolate brown suede shoe for the finishing touch.
I agree that this would work, not on, say, a court date, but maybe a more casual look for Friday or hump day. The black and white color combinatuon could look nice, done right, but IMO, would be neither here nor there for your work (you're a lawyer, right?) Seems too casual, and perhaps even offuppingly dandyish on a court date, and not casual enough for casual days.