A: If there are other Jews in the street, he does not require an escort. A bride and groom require an escort since they are similar to a queen and king. A mourner, however, requires an escort so he will not be alone, and if others are in the street, he will not be alone. See Piskei Teshuvot 239:11 (When Rav Aviner was sitting Shiva for his mother z"l, he came to the Yeshiva one morning so that the students could pay a Shiva call without having to travel far and thus missing Torah learning. He told me that when he walked through the Kotel Plaza, he did not require an escort, but when he walked through the so-called Muslim Quarter he would need one).