When "bad" people embrace sadhana, does god absolve them? If God absolves them, then the morality and ethics are mere societal constructs to gain control?

I am a beginner, and my questions appear naive perhaps. I use the general term God here but looking for answers from Tantra Sadhaks POV.

Where can I find answers to these questions? I held myself back from embracing the path of spirituality because I have seem dark people who have committed the worst of the sins in the name of god.Now with increased awareness, my knowledge and understanding has improved and I am embarking on this journey but the flurry of so many thoughts continue to be a bother. I understand it's a journey and I will figure it out these myself on my own time.

Do inherently bad people who have 2 or more personas all of them being a far fetched pretence - does god absolve them their bad deeds? Can people continue being bad and do sadhana and be an ardent follower of god and they are free of their sins? Again, this appears to touch on the deeper topic of Karma. But some initial food for thought will help me structure my thoughts and frame my queries better. Some guidance please :)