Women wear skirts or slacks. Professors and artists can dress more casually. In the autumn, winter and spring, men will usually feel comfortable with a suit, nice sports jacket or cashmere blazer with dark flannel slacks, and almost always a tie. Invitations to charitable events tend to be more dressy. In the summer outside, most men will feel at home with a nice lightweight blazer and sporty slacks.
Women can wear lighter colors and cooler materials.
Pack a swimming suit if called for. For the opera, opening nights, awards and charity events, some men still wear a tuxedo and women often wear long gowns. Churches, Synagogues, Mosques, etc. Ignore how some rude people dress. Depends if you are the lawyer or the defendant.