It's in your best interest to act with integrity
To make decisions with integrity, I make one change: when I imagine picking an action, I pretend that picking it causes everyone to know that I am the kind of person who picks that option. Integrity for Consequentialists - Paul Christiano
Should we deceive others into doing the right thing? Lie for their sake?
No. This is a place where rule-based thinking can lead us to the best outcomes. (Cultivating virtues is practical for better consequences).
Surely there are some situations in which there would be better consequences if you acted without integrity—in a way others would not approve of if they knew what you were doing.
Let's say I could produce fake climate data that's even more convincing than the real data, and it would lead millions of people to donate more money towards environmental causes.
The problem is that there are many hard to predict ways that this could go wrong on a long-term scale. Having your bad integrity exposed could lead to a loss of trust and a backlash that causes the opposite of what you wanted, such as even less people trusting climate science.
When acting without integrity, the truth will always be your enemy and will always have a chance of being discovered in the future. You could get away with it, but if it's something that's tempting enough and influential enough to try to get away with on the short-term, you will probably get similarly strong backlash if exposed.
(This is a theoretical example and I do not know the extent to which something like this actually occurred or not). Imagine that the US CDC switches it's COVID guidelines. They give out exaggerated information that they think will make everyone safest, instead of exactly what they believed. If people find out they were being partially lied to, they will trust the CDC less, take future recommendations less seriously, and therefore make everyone less safe in the end. One decision without integrity means people have good reason not to trust you in the future. You risk a ton of leverage, trust, and your ability to negotiate with others for a small short-term gain.
Acting with integrity is also simpler and easier, you don't have to make this hard decision about whether it's worth it to deceive this time if you follow the rule of acting with integrity.
TLDR:
Acting with integrity is easier and better for everyone over the long-term.
References:
Integrity for Consequentialists - Paul Christiano To make decisions with integrity, I make one change: when I imagine picking an action, I pretend that picking it causes everyone to know that I am the kind of person who picks that option.
The Precipice Don’t act without integrity. When something immensely important is at stake and others are dragging their feet, people feel licensed to do whatever it takes to succeed. We must never give in to such temptation. A single person acting without integrity could stain the whole cause and damage everything we hope to achieve.
Related: Enlightened Altruism