Your "negative karma balance" gets payed for by Jesus blood. Not when you're baptized, when you believe. The judge takes your death sentence for you, payed in full, past and future.
so, all I can do is hope my belief is enough and I actually have no control? Strong believer but a total asshole gets away? Screw that! It makes life pointless. Karma makes more sense
To clarify, from Ephesians 1 "When you believed, you were marked in him with a seal, the promised Holy Spirit, who is a deposit guaranteeing our inheritance."