Oh, I love to play the Sophist on this one.
Of course it is ethical to get out of jury duty. All duties are non-consensual, in that they are imposed by a superior power. One has no moral obligations to power, especially when that power works against one’s self interest.
In this case, the power laying claim to your most valuable asset, your time, and thus your obligation as a moral agent is to do all in your own power to frustrate that claim and to that end all things are permitted that are expediant.

If you can possibly serve without defaulting on some other even more important obligation, I believe you should. But I’m a self-employed person and the only earner in my household, so I have in fact asked to be excused several times. I suspect (sexist rant alert) that when a man says he’s in a moral quandary, he means he has to choose between what he ought to do (like jury duty) and what he’d like to do (like play golf), whereas when a woman says she’s in a moral quandary, nine times out of ten she means she has to balance two incompatible obligations.

I would consider it an honor to serve on a jury. Unfortunately, I only had one chance, years ago, and the notification hit me about a week before I had made arrangements to move to another state. The invitation was poorly timed. Had I not been in the throes of changing my life, I would have tried my best. The cause of justice is everyone’s concern. If everyone tried to duck jury duty, what would become of our country?

I believe that serving jury “duty” is the second highest calling a citizen has (the first is voting). Serving as a juror, just like voting, is our right as well as our duty because every man or woman has the right and need to have a fair and impartial jury decide his or her guilt or innocence. It is truly preferable, to me anyway, to have someone listen to my side of the story with enthusiasm and an open mind than to have someone who feels forced to be in a hot crowded room and wants to be anywhere else. I want someone who will listen to the facts of my case, not someone who can’t give me a few hours of their time while I fight for my life, my property, or my rights. I believe the last time a complete jury willingly served was when O. J. Simpson was on trial for the murder of his wife and Ron Goldman, and they only wanted to be a part of the notoriety of the case. That is wrong. As a responsible citizen, it is a duty that you impose upon yourself to maintain the freedoms that you wish to have in this great county of ours. If you perform your duty to vote, you should also serve. True, sometimes you need to be released from this service, especially if you are sick, will suffer financial harm, or are related in some way to the facts or people of a case. There are some other possible exceptions to this, but these are the main ones I can think of. Overall, it is truly unethical to “skip” jury duty just because you don’t want to be there.