Rule Of Law Offers Protection For Citizens
Law protects a society from anarchism. It is a set of conducts that is established and enforced by a sovereign authority to ensure and maintain orderly coexistence in the society  . Law refers to a “command proceeding from the supreme political authority of a state and addressed to the persons who are subject to that authority"  . Law helps the society, citizens and civilization to cohabit peacefully by providing them with a guideline about how to behave, how to act in social and business life, how to arbitrate the conflicts between multiples parties.
Rule of law is a general legal maxim  according to which decisions should be made by applying known principles or laws, without the intervention of discretion in their application.  This maxim is intended to be a safeguard against arbitrary governance. The word "arbitrary" signifies a judgment made at the discretion of the arbiter, rather than according to the rule of law. 
Albert Venn Dicey’s theory on the Rule of Law
In discussing the rule of law, the views of Albert Venn Dicey put forth in his “Introduction to the Law of the Constitution", are indispensable. To him the main components of rule of law are:
No punishment may be inflicted other than for a breach of the law.
Irrespective of rank and status all are equal under the law.
Rights and freedoms are best protected under the common law.
Rule of Law prevents the authority to use their power arbitrarily, and provides protection for the citizens:
Authority must not use their power arbitrarily:
Equality before law and avoidance of arbitrary use of power can be two important areas where the authority must decide wisely on how to enforce the law.
Equality before law:
Equality before law means every citizen in a given area will be treated equally before the law and there will be no discrimination or privileges to any particular group or individual. Without this fundamental characteristic, any law can lose its effectiveness drastically. If two different persons are treated two different ways just because of their social background then we could say it as a breach of equality before law and that would propel instability and violence in the society. Marxism  doubts that law represents the interest of the powerful within the society in modern world. International Bar Association combined the concept of equality of law with rule of law and said, “The Rule of Law is the foundation of a civilized society. It establishes a transparent process accessible and equal to all". 
In some cases we see that even the constitution might have conflicting position about ensuring the equality before law. For example, Bangladesh Constitution is said to guarantee the equality before to all its citizens.  But at the same time, it gives the parliament the authority to provide indemnity to any state officer, which might possibly sometimes breach the equality before law  , because all citizens are not treated equally.
Avoidance of arbitrary use of power:
An authority or government must not use their power arbitrarily. Sometimes certain laws allow them to practice some degree of arbitrary power over citizens, but that power is used unwisely, then it might become contradictory with the higher laws and constitution and promote injustice in the civil society.
For Example, In Bangladesh, section 54 of the Criminal Code gives the power to police to arrest an individual without the order from a magistrate and without warrant just on the basis on suspicion.  This is frequently used by Bangladesh Police force to pry information out of individuals after arresting them with arbitrary power. Dhaka Metropolitan Police often use another similar law which allows them to arrest any individual after dark whoever fails to provide any satisfactory explanation. 
Professor David H. Balyey said, “In India today, a dual system of criminal justice has grown up, the one of the law and the other of politics. With respect at least to the police, decisions made by the police officials, about the application of law, are frequently subject to partisan review or direction by the elected representatives." 
If these options are used randomly and on a regular basis without any knowledge of long-term impact, then it might pose a serious dissatisfaction among the public and cause instability in the legal environment. So government officials will have to decide wisely when and where to use them. Here again, the supreme power of constitution provides shelter to the citizens if they fall victim to any governmental arbitration. Bangladesh constitution safeguards against arrest and detention. It says, “Every person who is arrested and detained in custody shall be produced before the nearest magistrate within a period of twenty four hours of such arrest, excluding the time necessary for the journey from the place of arrest to the court of the magistrate, and no such person shall be detained in custody beyond the said period without the authority of a magistrate." 
USA PATRIOT Act  is a recent example of arbitrary power practice by the government. This law was enacted by US Government on October 26, 2001 mainly to fight terrorism but it denied appreciating one of the fundamental characteristic of US Constitution which is freedom of expression and privacy of citizens. This law gave the authority the power to search and spy on any form of communication in the country, detaining any foreign citizens without court order if they are thought suspicious. This sparked a lot of criticisms throughout the country, and provoked a lot of violence in the society. Here, the US government failed to uphold the rights of citizens.
Judicial Activism: A Possible protection against discretionary power:
In case of vulnerability of existing law, the Judicial Activism  can be a very timely solution for any country to protect the citizens from crime and discretionary power practice by the higher authority. Especially The High Court of Australia gives immense importance about judicial review of their existing laws.  Australian legal practices assure that there must be some minimum capacities of judicial review of administrative section  and the courts have a duty to exercise a jurisdiction which is regularly invoked  .
The importance of judicial review is, as stated by Brian Z. Tamanaha, “Throughout the so-called formalist age, it turns out, many prominent judges and jurists acknowledged that there were gaps and uncertainties in the law and that judges must sometimes make choices." 
Absence of appropriate law acts as an obstacle to prevent crime:
In many cases, it is seen that a country does not always have appropriate laws against all types of crime. Therefore, those crimes happen with very much ease. For example, software piracy is an internationally recognized crime, but in Bangladesh there is no solid law to prevent this. That’s why Bangladesh is at the top of software piracy in Asia Pacific  where software vendors lose 102 million US dollars every year  due to this crime, but no laws or government authority take any actions because of the absence of proper law.
Rule of law and Protection from Crime:
Thousands of years ago ancient Greek philosopher Aristotle coined the importance of law by stating  that "law should govern", and the higher authority who are responsible for the implementation of law should be "servants of the laws." According to another famous Greek philosopher Plato, law should be primary source of guidance for a country. He wrote  , “If law is the master of the government and the government is its slave, then the situation is full of promise and men enjoy all the blessings that the gods shower on a state."
And there comes the importance of rule of law. Rule of law prevents government from using its power at will, and ensures that the convicts can defend themselves in front of law. The rights of individuals are determined by legal rules and not the arbitrary behavior of authorities. There can be no punishment unless a court decides there has been a breach of law. Everyone, regardless of their position in society, is subject to the law, and held equally responsible. 
Therefore, Law is a formal and detailed code of conduct that shapes the economy, politics, culture and human rights in a country if it is enforced by a knowledgeable higher authority. The basic function of law is to protect the society from crime. A crime can be defined as any type of offense that goes against the civil society, for example, murder, theft, robbery, fraud, assault, copyright infringement, contract violation and so on.
Crime is inevitable in any society. The possible reasons behind committing a crime are being a victim, eyeing an opportunity to gain something and absence of a proper supervisory authority. This is where law of the country comes to play its part by bringing the criminal under justice, convicting them under certain penal code depending on the nature of the crime and declare certain sentences for that particular offense.
It is scientifically proved that human mind always gets influenced by its surroundings. All mental factors and actions of a human being are dynamically interrelated with social, economic, biological and psychological events happening around  . Hence, it is a tendency of human mind and civilization to learn from past experience. Therefore, when in a society people observe a criminal being convicted and punished they learn about the undesirable consequences of committing a crime, so that in future the rate of crime in that society decreases which is better for peace in the civilization.
An important thing to notice is, good legal environment always allow the convicted person to get opportunity of self defense, so that no innocent person is punished. The goal of sentence to serve in prison is to turn the bad person into a good one. Inside the prison the authority helps the prisoners to learn moral values and principles. So after coming out of the prison, they experience a changed and positive mindset toward the society, and they no longer act as a threat to the civilization and country.
Protection of human rights through constitutional law:
Constitution is a written document that describes the fundamental structure and procedures of a government in a given state. According to Scott Gordon, a constitution "contains institutionalized mechanisms of power control for the protection of the interests and liberties of the citizenry, including those that may be in the minority." 
Violation of human rights is prevented by strict application of constitutional law. In Bangladesh, if any citizen faces any violation of his/her fundamental human rights they are entitled to seek help from the law according to the Bangladesh constitution. It ensures the protection of law, equal rights, prohibition of forced labor, freedom of expression, freedom of movement, and equal opportunity for public employment for every citizen of Bangladesh. 
Another important aspect that has been clarified in Bangladesh Constitution is government cannot make any law that goes against the fundamentals of the constitution i.e., no law can be made that violate human rights or the right order in society. It says, “Laws inconsistent with fundamental rights to be void" 
Therefore, a constitution which is the highest law of a country should give protection to its citizens from any crime and arbitrary use of power by the higher authority.
Rule of law has its own strength for protecting human right, resolving dispute and establishing a peaceful society. It helps people to feel that there is always an invisible friendly hand who will act as a shield against the inequalities they face in their daily life. But it establishment is very much dependant on the sovereign authority of the state. If they fail to make the law equal to everyone, deprived citizen will then feel that law of their state is a tyranny for them. A government should enforce those laws which will go with the public interest, not for authorities’ own illegal purpose, not against the public sentiment. Because they have to know that law has a wide array of implications in every layer of the society.
Therefore, rule of law will protect the society from any kind of crime, anarchy, inequality and it will defense everyone to get their proper judgment. The authority of the state has the power to create a new constitution, a new law. But that doesn’t mean that they can do as they wish. All are equal in law. Everyone has to be stood in front of law if any unlawful thing happens. So not only the public but also the government, the sovereign authority must have to obey the law and have to make the proper use of law to protect the civilization from any hazards.