The United Nations bans torture, and all member nations are expected to follow these regulations. With that in mind, international law absolutely bans such actions. The United States and many other countries have chosen to ignore these edicts, which is a bad idea. No country should unethically torture human beings.
Torture is considered illegal under the Geneva Convention and it is something that is not supposed to happen even in the time of war. So torture is absolutely something to be considered illegal, and for good reason. Torture taints everybody that it comes in contact with and ruins the integrity.
Yes international law does in fact ban torture of individuals. This does not mean that it is not done though. There are many countries that pay no attention to international law. The countries that do hide the torture so that they are not subject to sanctions and punishments under international law.
The Geneva Conventions ban torture under international law. Prisoners of war should be treated fairly during their capture. We don't live in the Dark Ages. Instead, with electronic surveillance and modern methods, we can extract intelligence by means other than torture. There is no need to torture someone anymore except for pure sport, which is absolutely barbaric.
The use of torture is banned under international law. This raised some controversial questions in the US a few years back due to our admitting that we used torture or 'enhanced interrogation' techniques in order to extract information from Al Qaeda operatives. No matter what, torture is still viewed as illegal and a war crime.
The world is becoming a smaller space because of the ease in communications. The United Nations mandates that civility be used in the use of getting intelligence information for an example for a prisoner of war. In that regards. countries of the world agreed to not exert torture for information.
Torture is not banned under international law. There are many countries that engage in torture, and banning it would not help in any way. Those countries would continue to use torture as a way to gain information and would have an unfair advantage over countries to have agreed to not use torture.
Torture that is carried out correctly and efficiently can be very useful. You need to ask a question that you already have an answer to. Then you can tell if the person is going to lie the whole time, if that is the case then that person is useless to you.