Being a president is a big responsibility they have big burden on their shoulders. Some people, when they are under pressure seems to make wrong decisions and they should not be held up for it. If a sport players makes a mistake during the game and gets away with then I don't think why not the president. But on the other hand president have to be careful because their decision matters more then anyone else.
Nobody should be pardoned for their crimes. Do not commit the crime if you can't do the time. Rich people are the only ones who get pardoned anyway. Pardoning serves no positive purpose to the citizens of society. Criminals will always be criminals regardless of what the president says about it.