In order to get to the Kotel (Western Wall), the visitor has to undergo the regular security check. There are four entrances to the Kotel Plaza and each entrance is secured by private Israeli security guards. Policemen are around but the cops themselves do not carry out the security checks but a private security company.
In the past, I have heard many complaints about those private guards. Almost all of them used to be Ethiopians and quite a few religious Jews felt mistreated by them. Especially when it comes to the security scanner being used on Shabbat. During the week, every visitor has to go through an metal detector door where it beeps as soon as someone is carrying a metal device. Then pockets have to be emptied out until the detector doesn't make any noise anymore. But what about Shabbat ?
There were guards who wanted to force religious Jews going through the detector on Shabbat. The detector itself either gives a green or red light to the guard. Religious Jews refused undergoing this procedure on Shabbat, as causing a light to go on is a Chilul Shabbat. I myself saw many guards running after religious Jews trying to force them into the metal detector and threatening them with getting arrested. As far as I saw, now most guards are born Israelis and not Ethiopian anymore. Visitors who don't want to undergo the detector precedure on Shabbat may empty out their pockets and just pass the security.