Earlier quoted context omitted.
Sorry to break it to you, but as with many things in the US constitution, the reason the President can pardon people is because it's a modified copy of the British constitutional system of the time. The House is Parliament, the Senate is the House of Lords, and the president can pardon people because King George III could and the office of the presidency is a limited term elected kingship. Executive orders are Royal…
While pardon power originated from British law, the reason we kept it was what the OP referred to (see the federalist papers [1]). When forming the government the founders didn't just blindly copy British government. There was a lot of debate over what to keep and what to omit (For example, we don't have a king. Presidents were seen as servants not as rulers). Pardon power is mostly a direct copy of British pardon po…
The British system was very familiar, and while it had potential flaws visible to them at the time they were known familiar flaws. I find it doubtful that someone coming up with an entirely novel and unfamiliar system would have got anywhere at all, no matter how rational and well argued it was. People like familiar and that can affect their judgement. Just worth considering.