THE PRESUMPTION OF INNOCENCE
Our legal system is based on the presumption that everyone accused of something until they can be proven innocent. In a civil claim, the presumption is that the person did not do what they were accused of as well. That means if you think that someone has done something wrong (whether it is the prosecutor or a plaintiff) you have to overcome the presumption that the person didn't do what you say they did.
Whew, that may or may not have made any sense. So, let me see if I can break it down a little bit more.
Legally, a presumption is something that we need no proof to believe. It is the default position. If no one has any evidence you have to believe that they didn't do it. So, how do you prove that the person did what they are accused of?
GREAT QUESTION! I'm glad you asked.
It depends on the type of case we are looking at. In a civil case (you sue someone because they crashed into your car, or because they threw a tarp over a pit and you fell in it) the "Burden of Proof" is the "Preponderance of the Evidence." That means you have to prove it was a little bit more likely than not that what you say happened actually happened. 50.0000001% more likely that what you say is what happened rather than it didn't. If you have a scale (you know like in legal shows that the angel of justice is holding a blindfold on) then on one side you placed "THE PRESUMPTION OF INNOCENCE" you would have to put enough evidence on the other side of the scale to just every so slightly tip the scale over.
In a case where we are looking at family law, custody of a child, what is in the best interest of a child, equity, and a lot of other things (too many to really list) you have the Burden of "Clear and Convincing Evidence." That means enough that you are convinced. More than in a civil case, which is only more likely than not. You have to show enough evidence that would convince someone. Is that 55%? 60%? 90%?! Well, I can't really tell you that. They don't let you throw down numbers like that. It's more than "preponderance of the evidence," but not so much that you have to erase all doubt. It is a fairly high burden of proof. If you can't put together enough evidence to convince the jury, then the jury should presume that the child is not in danger, that custody doesn't need to be changed, etc., etc.
Criminal cases have the absolute highest standard of evidence. We presume that the accused DID NOT commit the crime they were charged with unless there is enough evidence to show, "Beyond a Reasonable Doubt," that they actually did it. A reasonable doubt is not that magic could have made it happen, or that maybe it was the aliens that got them. Rather, enough evidence that there is no other reasonable explanation for what happened. This is more than the preponderance of the evidence, MORE even than clear and convincing. You have to completely overrun any reasonable explanation. It is a higher burden than most people realize.
Think about it like this, if you are ever on jury duty and they ask "Do you think they are guilty, innocent, or are you undecided?" If you answer "Undecided," that means you think they are innocent. By default. If they have not given you enough information to do MORE than just convince you, then you must presume that they are innocent of the charges. If they have not removed all reasonable doubts from your mind then that person deserves to go free.
In our society, we decided, a long time ago, that we would rather see a guilty man go free rather than see an innocent man put in jail. Jurors don't always follow that rule, but if you ever are on a jury make sure that you really think about what they have proven before you decide to find them guilty.
Good luck out there.