in (all) conscience

in (all) conscience

Without guilt. Usually said to emphasize fairness in a transaction. Primarily heard in UK. In all conscience, I can't charge you more than the car is worth. No, I can't, in conscience, give you a better grade when you put such little effort into the assignment!
See also: conscience
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

in conscience

Also, in all good conscience. In all truth or fairness, as in I can't in conscience say that the meeting went well, or In all good conscience we can't support their stand on disarmament. [Late 1500s]
See also: conscience
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

in (all good) conscience

In all fairness; by any reasonable standard.
See also: conscience
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
See also: