If you say that you cannot do something in all conscience, in good conscience, or in conscience, you mean that you cannot do it because you think it is wrong.

What does acting in good conscience mean?

in (all) good conscience

Fig. having good motives; displaying motives that will not result in a guilty conscience. ... She had only been acting as a good citizen should.

How do you use good conscience in a sentence?

without feeling guilty: You couldn't, in good conscience, ask her to pay the whole bill!