Is Utilitarianism is a moral theory that focuses mainly on one's intentions?

Answer 1

No, it focuses on opinions.

If it is your opinion that intentions mean more than actions, then your relative morality does.

If it is another's opinion that actions mean more than intentions, then that other's relative morality doesn't.

Relative morality is just the variation in moral opinion from person to person, or from society to society on a larger scope. It doesn't give any values or demerits in and of itself.

Answer 2

No.

As a general principle, utilitarianism focuses on the outcome of an act. It is interested in the usefulness (utility) of any given act in maximising what is considered to be "the good". So if a specific act increases the "overall good" then it is considered the right thing to do under utilitarianism. Whether such an act is morally correct is therefore determined by its outcome (if it maximises "the good") and not the intention of the person acting.

So if I bought you a box of chocolates for your birthday (because I intended to try and maximise your happiness), but unknown to me you were allergic to chocolate and became ill after eating them, then the fact that my intention was good is irrelevant according to utilitarianism. I would have failed to maximise the good and my act would not have been correct.

There are different forms of utilitarianism, and the above may not apply exactly to each of them, but as a general principle we can see from this that it does not focus mainly on one's intentions.