Shekalim 21
a saliva in the middle of the road – we presume from a tame person, as he would not be careful and walk in the middle. on a side – from a tahor who was careful. Except during holidays – most people going to Beis Hamikdash are tahorim and go in the middle. Whoever is in a majority goes in the middle.
Implications:
– you can evaluate person’s status by where and how he walks (not judge, evaluate for halakhic decisions)
– where majority is in masks, maskless people should walk on a side of sidewalk (or on the road?). in places where majority is maskless, masked people walk on a side. No machlokets, respect the local majority.