My Question involves a halachic bris.
How does one know that they are halachically cirumcised? What are the halachic requirements for a mohel, must he be shomer shabbos/yiras shamayim to perform a bris? If a person grew up in a non-frum environment how do we know that a bris was performed in accordance with halacha? Thanks for your help!
One can always assume that a bris was conducted in a halachically correct way.
One reason for this is as the Gemara writes concerning meat that was ritually slaughtered: Most shochtim do so properly, so we can assume that the meat is kosher. The same it true for circumcision.
However, with regard to circumcision this is all the more true, because there are no formal requirements for a mohel, and no delicate halachos as we find in shechitah. If the bris looks fine, there is therefore no concern.