If your colleague is doing something against the company rules, however doesn't affect you, would you tell your team leader?

I believe my  first step would be to talk to my colleague. I would need to understand what he/she did and why and then reason with him/her to set things straight.

If this doesn't work out there is still time to talk to my team leader.

Most companies have a whistleblowing policy in place to handle a situation such as this. This encourages and enables employees to raise serious concerns within a structured and secure manner. More to your question, if a colleague is doing something against company rules then you should report it because if it is exposed in an uncontrollable way then the organization can potentially suffer a huge reputational loss and that in turn will affect your employer as well as your own future employability… would you hire someone from Arthur Andersen or Enron Corporation?  If someone had blown the whistle inside these companies, they may have existed today.

Regards,

Ali

First I'd assess how that is going to affect the company, going against a rule doesn't neccessarily mean against the well being of the company. If that can bring some positive changes in the company then I'd ask my colleague to discuss first with Team Leader.

If going against the rule is not in the interest of company then I'd try to convince him, if he would not mend his ways then I 'd inform our Team Leader

tell him personaly to stop this action against company . if have no it must be report to team leader  with valuable evidence other wise we might be loos the business and team leader take a strict action against him. please note that company giving salary for us . so, we have to give a good support with out company lost.

Sure I will, After advice my colleague ..if there is no hope....

aCCORDING TO BUSINESS PROFESSIONAL ETHICS , WE SHOULD ADDRESS UNPROFESSIONAL or/and BAD ATTITUDE, in which at the end such attitude will reflect against the whole enterprice activities.

I echo with Wolfgang Christoph Altenstrasser.

Yes off course as it may effect us if TL is misleaded

In my honest opinion, I would probably tell my team leader that the other employee is doing something against the company rules although it does not affect me directly. I believe the purpose of a team leader is to be in control and maintain good communications with his subordinates. However, if one of his subordinates does violate company rules, it is his duty to warn the other employee the consequences of his actions if he is proven guilty of misdeed of company rules and/or policy.... A good leadership is a moral that boost employees good relationship with the leader and the company itself...

talk to him .If he doesn't respond.I will talk to the leader.We are in the same boat and his mistakes will let the boat sink.

You should after confirming that your assumption is correct.