A couple of years ago, the deputy mayor of Richmond Hill, Ontario attended a Lubavitch menorah lighting and was stunned when the Chabadnik rabbis running the event refused to shake her hand. The initial two reponses to the incident were typical. One group, led by the deputy mayor, played the selective cultural tolerance card, that is: in Canada we're multicultural and tolerant of different ethnic groups... until they break the rules of political correctness. The other group played the non-selective cultural tolerance card, that is: in Canada we're multicultural and tolerant of different ethnic groups, no matter how kooky we think their customs are.
A suprising middle ground was staked by The National Post's Barbara Kay. Despite being a decidedly non-observant Jew who has, on multiple occasions, happily demonstrated a hostile attitude towards Orthodox Jews who have the gall to actually expect to have their rights respected in a secular world, she managed to pull off something I never would have expected. After writing a column based on emotion, she went a step further and found a teshuvah by a bonafide Modern Orthodox posek, Rav Yehuda Herzl Henkin, which permits men and women to shake hands in certain limited situations. This, she concluded, shows that the Lubavitchers were not acting in accordance with the Jewish Law they claim to observe so rigorously. If they were, they could have used this teshuva to support their shaking hands with the deputy mayer and avoided the whole confrontation.
It sounds great. It certainly is better than simply shouting insults and accusations. And it misses the point of the halachic process completely.
The principle difference between the Chareidi and Modern Orthodox communities is their approach to halachic consensus.
Within the Chareidi community, the system is simple. If you are a chosid, your Rebbe decides the rules. If you're Litvish, then you have the designated heirarchy starting with Rav Eliashiv, shlita, and moving on down as well as a list of approved poskim whose works are considered authoritative. A teshuvah from a unapproved or non-recognized source, no matter how scholarly, is a non-starter because it comes from outside the approved framework. A Dati Leumi rav could write the perfect teshuvah showing that all religious Jews should undergo compulsory military service in Israel. It'll never be mentioned in Chareidi circles, let along quoted, because it's not part of their system.
The Modern Orthodox system, on the other hand, seems to approach the idea of halachic decision making from the diametrically opposed position. Any teshuvah, any schoarly piece of work, whether by a known posek or a particularily gifted university profressor, carries equal weight when the time comes to make a decision. Rav Eliashiv and Professor Marc Shapiro both get an equal say. As a result, a Modern Orthodox person looking for the answer to an important question has a wider range of sources to choose from and greater flexibility of answers available. Does he want to shake the local female official's hand? Great, we have Rav Henkin's teshuvah. He doesn't want to? Fine, this time he'll hold with the Igros Moshe. As the old saying goes, where there's a halachic will, there seems to be a halachic way.
The problem is that this turns the whole concept of halachic inquiry within Modern Orthodoxy into a joke by removing any standards. It leads to a behaviour that decides that even when a favourable teshuvah can't be found, the desired answer can still be provided because ultimately that answer has been predecided and requires only the thinnest veneer of halachic cover.
Ultimately the cure for this problem is for the religious leadership of Modern Orthodoxy to take a stand and curtail the rampant personal autonomy that is leaving the movement without direction or coherent form. There is nothing wrong with Modern Orthodoxy saying that the teshuvos of Rav Henkin, for example, are authoritative but that means accepting the "bad" with the "good". (For example, Rav Henkin may be realtively liberal about handshaking but he has rejected the newest left-end MO trend, the partnership minyan) It means that if you're going to reject a psak by Rav Eliashiv or one of his successors, it's because you have a psak from an MO authority that you follow, not because Rav Eliashiv is "another one of those crazies from Israel". Until Modern Orthodoxy does this, there's no compelling reason to bandy any teshuvos around. No one really believes they care about that.