From which threat you are asking of protection? But yes I want to mention that the contracts fixed with Bitcoin as a payments option are fully protected as many people have fear about this. The local laws are always applicable as long as your contract is legal. Everything will take place as usual, ONLY THE PAYMENT method will change. The only requirement is that this should be explicitly mentioned in the contract that you are making payment in Bitcoins. After this if the other party refuses to fulfill the contract you can seek legal help.