The law's an xxxxx

Just watching the news about looking for the person who murdered the policeman.  What gets me that if he's found and sentenced to life, he will no doubt appeal his sentence that its too long.  I know people have been jailed wrongly, have been freed and given compensation - and I applaud it.  But at the same time it should be the same at the other end of the scale.  If they appeal because their sentence, for example, is too long, should have an extra 10 years added to it