Is Malaysia an Islamic State?
For answering that question, Malaysia is a country that is in between of Islamic state and Secular state due to some reason. First and foremost, definition of a country to be an Islamic state are according to various Muslim Scholars: Firstly, according to Muhammad bin Hasan Asy Syaibani stated that “The state controlled and ruled by Muslims and Muslims enjoyed peace and tranquility in it." Then, based from Muhammad Abu Zuhrah "The Islamic State is a state that is under the dominion of Islam. Strength and its defense dominated by Muslims. Such countries must be maintained by each and every Muslim". Another character of an Islamic State is where Syariah law is being enforced and implemented all over the territories. From the definition above, it can be said that Malaysia is an Islamic state as Muslims are the controlling party and the Head of Government and Head of Nation are Muslim. After that, Muslims citizen enjoy and freely practicing Islam. But as in the context of implementation of Syariah Law (Islamic Law), we are not enforcing Syariah Law fully in our nation. Besides, Islamic law only applicable in personal matters such as marriage, divorce and inheritance. It is conclude under state matter, not being a paramount rule as federal constitution. Malaysia it's just an ordinary state that recognizes Islam as the official religion of the country.
To support that statement, Article 3 of the Federal Constitution states that Islam is the religion of the Federation. But other religions may be practiced in peace and harmony in any part of the Federation. So Malaysia can’t be a secular state by virtue of having an established religion. It is worth mentioning that there is no authentic interpretation of the Constitution in Malaysia and somehow word "Islam is the religion of the Federation" in the Constitutional translated incorrectly as "Islam is the base religion of the Federation".
If we refer to cases decided in court in Malaysia there are a number of old cases that give meaning to narrow the word "Islam is the religion of the Federation". In the case of Che Omar bin Che Soh v Public Prosecutor  2 MLJ 55 the arguments made on behalf of the appellants is the death penalty mandatory for trafficking in dangerous drugs and possession of firearms is against the teachings of Islam and therefore null and void. Argued that because Islam is the official religion, the death sentence imposed on the offense, not offense, "hudud" or "qisas" according to Islamic law, is contrary to the teachings of Islam and therefore invalid under the Constitution. Although Salleh Abas, the chief justice at the time, when giving judgment no doubt have said Islam is not just a set of beliefs and ritual alone but is a complete way of life that includes all areas of human practice, whether private or public, on the legal, political , economic, social, cultural, moral or judicial, and how to set up all manner of life including the laws and morals are guided by the revelation of God found in the Quran and the hadith of the Prophet but he asked the meaning of Islam is that intended by the makers of the Constitution? He has refer to the history of British entry in Malaysia as occupiers for which they have divided religions into two types, one in personal matters and in terms of the public. In all areas including administrative law and justice, they have waived Islam and apply secular manner. Therefore only Islamic law on family and inheritance are allowed and then only apply to Muslims. Results from the British colonial era, Islamic law has been isolated in a narrow range on the law of marriage, divorce and inheritance. This is the meaning of "Islam" which intended by the makers of the Constitution. The decision of this case is an important statement of the status of Islam. Although recent times have seen the “islamisation” of the nation, the case provides a clear view that Malaysia is not an Islamic state but a secular state with Islamic characteristics and bias.
According to the Article 11(1) stated that every person has the right to profess and practice his religion and, subject to Clause (4), to propagate it. It is clear from the provisions that the Muslims have the right to profess and practice his religion, namely Islam as their way of life. Clause (4) stipulates that the law can be made to control or restrict the propagation of any belief among persons professing the religion of Islam.
On the other hand, in the interpretation of the constitution as that found in Article 160, Islamic law is not explicitly included in the definition. Provisions just mentioned, "By including statutory, common law, insofar as they apply in the federal or any part thereof and any custom or usage having the force of law in the federal or any part thereof. (Reference: Introduction to Islamic Law in Malaysia; Mahmood Zuhdi - Publisher UM) Former Chief Justice, Tun Muhammad Suffian hasyim stated goal of Islam (the religion of the federation) was originally incorporated solely for the ceremony, for example, to allow prayer to be read in the official ceremonies such as the coronation of Yang Dipertuan Pertuan Agong, Independence Day and other occasions. (Reference: Muhammad Suffian Hashim, Tun (1962).
What comes second is, approach to add “official” word is merely a political strategy when the nation gained independence and dealing with emergencies resulting from a communist threat that do not believe in god. For the avoidance of non-Muslim communities continue to abstain from participating in the new government, then such an approach made by politicians at the time. Based on the belief that the behavior has continued to spread secular ideas in the administration of the State. Principles and teachings of Islam are not able to control and monitor the activities of government and state whether in policy or law.
In conclusion, even though Islam as a religion is accepted by the federal constitution, but the reception does not make Islam as the Law of Nation. The word "official" is just a bonus, but its impact has been misleading all parties and create the wrong impression about the position of Islam in the country is to become "Malaysia is a secular democratic state with Islam as the official religion." The fact that these three words: democracy, secular and officially do not exist at all in the Constitution.
p/s: some opinions may vary that regard Malaysia is an Islamic state. well it falls upon our own judgment and opinion then :)