Quote Originally Posted by gilmore View Post
But then I believe you are in the UK. Here in the US the policies on dress have become much more relaxed.
I don't agree. The guiding framework is always local custom. The guiding framework to violations of local custom is "does the person know any better".

10% of American Jews according to the JJPS survey see themselves as "Orthodox" . More than 500,000 of which are Haredi. There has been a strong shift in the U.S. towards more Orthodox positions over the past 20 years in response to Reform (1/3 of American Jews according to the JJPS survey) and high rates of assimilation. Reform and Conservative communities are in strong decline. The Satmars (often associated with Neturei Karta) are, for example, the fastest growing and largest (Haredi) community with over 100000 members (in the township of Kiryas Joel in NY there alone at least 15,000 Satmars). The distribution is geospatial. In Williamsburg, Boro Park and Crown Heights (Brooklyn) or Monsey (NY), for example, most Jews are Haredi. Of the 600,000 Jews in Greater Los Angeles most are Hiloni (secular) but most Synagogues are Conservative. These communities too are in slow decline and realignment with a growth in Modern Orthodox and Haredi. In places like San Francisco the growth is in liberal movements (nearly all Jews in the Bay Area can be divided into Reform and Secular with Orthodox representing well under 3% of the population).

What's fine in one community can define expulsion in another.

While many Reform communities might seem "relaxed" (part of their philosophical core), the trend among many of American's Orthodox is in the other direction. While women in pants is not accepted by Modern Orthodox as Synagogue attire its considered fine for women on the street. Many communities are less modern. Rabbi Leib Tropper of Monsey, for example, retroactively reversed a conversion and annulled a marriage of a woman who had been "seen wearing pants on the street" or gone out without head coverings.

Usually synagogues, as well as most other houses of worship, are more intent on encouraging attendance than ensuring that congregants are properly attired.
The issue is not sartorial but ethical and philosophical. A woman wearing pants, a short skirt or short sleeves to an Orthodox Synagogue will be politely told by the women "the norms".

The last time I went to a synagogue on a Friday evening, last December, I don't believe there was a necktie to be seen among the entire congregation.
The use of neckties varies from community to community. Ashkenazic Misnagdim, for example, nearly always wear ties. Most Hasidim other than Lubavitcher, by contrast, don't typically wear them. Sephardi tend to not wear neckties but some of the affluent communities have adopted more European styles of dress including suits and neckties. Among most communities there also tend to be differences in attire between Kabbalat Schabbat (Friday Evening), Shacharit (Sat. Morning) and Mincha/Ma'ariv (Afternoon/Evening) prayer.