Should Upholding Ethics be left to an Individual's Conscience

As part of an organization, we all should uphold the business values that bind this organization into a strong being! There are miscreants though who neglect these values or simply stupid enough not to know basic ethics.
They as individuals dont mean harm to anyone, team, or a unit. But the selfish-ivory tower existence attitude they put up, make them do things that can and has caused harm to their own image, how they are perceived, and the group they belong to.

We all know of this saying, "One bad apple can ruin the whole basket!"
Thinking on these lines, we must note this corollary..."The moment the bad apple is found, the whole basket is put on the less value deck, the back burner."

Each one of us work at organizations that encourage us to follow some ethics and conduct. Almost all of us have undergone mandatory trainings that have shown us what is correct and what is not.
And, once the training is over... It is left to us, each individual, to practice and abide by these ethics. So, it now becomes more of our conscience to follow them.
The Ethics policies also mandate that in case we do see a violation of ethics and conduct, we must report it to our supervisors or a helpline that will file an investigation in to this violation.

Now then, here's where I feel comes the catch... Here's where we become "Trishanku".

If I see a violation of conduct in a team and do not report it (because reporting the violation might bring harm to someone), don't I violate the conduct myself?

So coming back to the post heading, and may rephrasing it a l'il bit,

Isn't it a risk to leave the responsibility of upholding ethics to an individual's conscience?

I leave this question open.

May be, I might get an answer myself.

Ending notes:

A Travelling Lighthouse I am,
I observe a lot of things, that one can't see normally.

Although my line of sight is a circle,
It's set on things, globally.

I shed light on various things, right and wrong, but why don't I utter a word,
All I see now, it's a long winding road ahead.