There are no laws in Oceania from 1984, why then is it such a terrifying and repressing place?
The answer to this question lies in the dual nature of laws - on the one hand, they exist so that people will know how to behave, and on the other hand, they exist to protect people from arbitrary accusation and persecution. For example, if there is a law that says that everyone must stop at red lights, drivers know that if they do not do this, they will likely receive a consequence, in the form of a ticket. Conversely, if a driver is given a ticket for not stopping at a red light when, in fact, the light had just turned yellow, that driver can defend himself by showing, through witnesses or other evidence, that he did not break the law that says he is to stop at red lights, because the light was not red when he passed through. Laws delineate the boundaries of behavior so that everyone is on the same page.
In Oceania, as stated in Chapter 1 of 1984, "nothing was illegal, since there were no longer any laws," but if Winston was caught writing in his diary, "it was reasonably certain that it would be punished by death, or at least by twenty-five years in a forced-labor camp." It might be argued that the law against writing in a diary actually exists in a sense, because everyone knows that it is forbidden to write in a diary, but since the law is unwritten - technically, there are no laws - a person would have no recourse if he feels he is being punished unfairly. The government has unlimited and ultimate control in Oceania, which is why it is such a terrifying and repressive place. A person can be vaporized just because the government believes that he has violated one of its unwritten laws, or really, for any reason whatsoever. In the absence of a clearly delineated code of conduct to which both the accuser and accused must adhere, there is nothing that the victimized party or anyone else can do about it.
Simply put, there are no laws in Oceania because the Party has so much control over the citizens that it does not need any. To understand this, think about how the Party pervades the lives of its constituents. It watches over every single one of its citizens with the telescreen, for example, and monitors all conversations through hidden microphones.
The Party also determines the content and flow of information to the citizens of Oceania, meaning that the Party dictates what is true and what is not.
The Party is also responsible for keeping its members fed, clothed, and housed. Even razor blades and chocolate are controlled by the Party.
The Party is also developing its own language, called Newspeak, in order to make it impossible for citizens to have any negative thoughts about the Party and the way that it governs the country.
The Party, therefore, has no need for laws because it makes it virtually impossible for any citizen to do anything wrong. Through a system of emotional, psychological, and physical control, the Party has brainwashed its members to do exactly as it dictates, without question and without complaint.