Neither Ethical Nor Healthy

The obligation to judge favorably is incumbent on every Jew - man or woman - at all times, and in respect to every Jew - man, woman, child, or adult. Although there is no Torah commandment not to suspect a non-Jew, nevertheless, it is neither ethical nor healthy to be suspicious of anyone, and it can cause a breakdown of one's fine character traits. One should strive constantly to maintain peaceful relations with everyone and to live in harmony with all.

(Mishpetei Hashalom)