Those who observe duty ethics are called Deontologists. Deontologists base their moral thinking on general universal laws, and not on the results of particular acts. (The word comes from the Greek word , meaning duty.) It is a form of moral absolutism, but some claim it is slightly different.
An act is therefore either a right or a wrong act, regardless of whether it produces good or bad consequences.
Deontologists don't always agree on how we arrive at 'moral laws', or on what such laws are, but one generally accepted moral law is 'do not tell lies'.
If we are truly concerned with the rights it seems only logically that we try and minimise the violation of these rights. However, deontological constraints themselves prohibit such action. For example, consider a case where someone has maliciously sent a trolley hurtling towards five innocent and immobile people at the end of a track. The only way to stop the trolley and save the five is to throw one innocent bystander in front of the trolley. If the five are killed, this would constitute five violations of the PPH. If the one is thrown in the way, this constitutes one violation of the PPH. However, the Principle of Permissible Harm clearly rules out throwing one in front of the trolley. Hence the paradox. In order to respect the rights of the five, deontologists tell us we must respect the rights of the one.
Kant had his own form of deontolism in which he defined that the demands of moral laws are categorical imperatives. Categorical imperatives are principles that are intrinsically valid, they must be obeyed in all situations and circumstances if our behavior is to observe the moral law. It is from the Categorical Imperative that all other moral obligations are generated, and by which all moral obligations can be tested. Kant also stated that the moral means and ends can be applied to the categorical imperative, that rational beings can pursue certain "ends" using the appropriate "means." Ends that are based on physical needs or wants will always give for merely hypothetical imperatives. The categorical imperative, however, may be based only on something that is an "end in itself". That is, an end that is a means only to itself and not to some other need, desire, or purpose. He believed that the moral law is a principle of reason itself, and is not based on contingent facts about the world, such as what would make us happy, but to act upon the moral law which has no other motive than "worthiness of being happy". Accordingly, he believed that moral obligation applies to all and only rational agents.