Arguments of this form assume that since something has not been proven false, it is therefore true. Conversely, such an argument may assume that since something has not been proven true, it is therefore false. (This is a special case of a false dilemma[i], since it assumes that all propositions must either be known to be true or known to be false.) "Lack of proof is not proof."
For example, since you cannot prove that ghosts do not exist, they must exist. We can substitute almost anything for ghosts and have the same effect. Or another example, since scientist cannot prove that global warming is happening, it probably isn’t. Since I cannot prove that gods do not exist, they must exist. I hear that one a lot.
This is what happens so often in debates and discussions about the existence of God. The person arguing that god does exist will attempt to shift the burden of proof to the non believer. I cannot prove that god does NOT exist so therefore he must exist.
In a court of law this kind of assertion would be laughable. Circumstantial evidence is well known in the courtroom as being very weak evidence, if evidence at all. Yet in daily life it is used with impunity. Scientists largely assume something does not exist until it is proven to exist, which is the base position in any premise. i.e. innocent until proven guilty. So, where the burden of proof lie? In a court of law it is with the prosecutor.
Therefore, until a believer can provide proof of the existence of god I will remain an atheist. I have no burden of proof and one cannot prove that something does NOT exist.
For the top ten arguments for the existence of god see http://freethoughtpedia.com/wiki/Top_ten_arguments_for_the_existence_of_God