Depending on your speach skill level and the nature of your crimes I think this is actually a pretty cool idea. High levels should pretty much get away with anything for a hefty fee. I say get away with just about anything because it would be pretty silly if you were able to go on a killing spree and kill 20 people, have the town guard or militia or whatever catch up with you and be able to pay them 20,000 gold or something to get of scott free. That would be bad. However if the crime was rather petty, like theft then you can bribe the guards to get away with it. Low speach means you have to give the guard the stolen items as part of the bribe and a large fee of gold. High speach means your able to pay a small ammount of gold and walk away with stolen goods. It all has to be within reason though because if you think about it and allow bribes for anything you could become a phycopathic murderer/theif and get away with it if your pockets are deep enough.
It should work too on an induvidual basis. The bribed guard would then turn the other cheek, if more than one guard sees your crime or whatever then your going to have to fork out the money or bribes will become redundant and usual being caught by the guards speach will appear. This does ultimately depend if the guards in skyrim will be omnipresent like they were in oblivion.