Is A Person Who Uses Unfiltered Internet Kosher as a Witness?

Can a Person who Uses Unfiltered Internet be a Kosher Witness? 

A mechalel Shabbos (one who desecrates the Shabbos) is pasul l’eidus (not acceptable as a witness in a Jewish court of law). Even if a person does not desecrate Shabbos b’farhesyha (publicly), if they desecrate the Shabbos b’meizid (knowingly) they are not accepted as a witness. However, a mechalel Shabbos b’farhesyah is pasul l’eidus even if they are tinokos shenishbu (raised without an appreciation for Yidishkeit). If a person commits a transgression on purpose for which they would incur malkus de’Oraysa (lashes ordained by the Torah), they are pasul l’eidus min haTorah (Biblically invalidated as a witness). If a person commits an aveirah d’Rabbanan (transgresses a Rabbinic law), they are pasul l’eidus mid’Rabbanan (disqualified on a Rabbinic level from being a witness). A person who is chashud al arayos (suspect of forbidden relations)—which  according to many poskim includes hugging and kissing, even if no forbidden relations took place—is pasul to be an eidus for testimony involving marriage and divorce. 

Contemporary poskim address the question whether people who watch television or use unfiltered internet are acceptable eidim. If a person who is known to be a yerei Shamayim, careful b’kallah ke’vachamura (with all mitzvos equally), uses unfiltered internet we may assume that they are moreh heter (convinced themselves that it is permitted), since lo mashma lehu l’inshi isura (people don’t think it’s actually forbidden) to use unfiltered internet, and therefore their testimony would be accepted after the fact. Nonetheless, even taking this into consideration, it would be wrong to use such a person to be an eid l’chatchillah. 439

https://halacha2go.com?number=439

Practical Halacha: One minute a day. By Horav Yosef Yeshaya Braun, shlita, Mara D'asra and member of the Badatz of Crown Heights.