European Law versus National Law
The European Union (EU) is constantly accused of invading the nooks and crannies of national life. In 1974 Lord Denning famously compared what is now EU law to ‘an incoming tide’ that ‘cannot be held back’. By 1990 he considered EU law had become ‘a tidal wave bringing down our sea walls and flowing inland over our fields and houses—to the dismay of all’.  More generally, citizens lament the erosion of national sovereignty in areas such as policing, border control and national security; they feel too much politically sensitive decisionmaking occurs at EU level.  Concurrent with the claim that the EU does too much, is a claim that the EU does not do enough. As the 2001 Laeken Declaration recognises,  citizens demand that the EU be empowered to do ‘something’ about key issues such as terrorism, immigration, employment and the environment. 
European Union Law designates the juridical norms which apply in the juridical order of the European Union, comprised in the institutive treaties of the European Community- Paris and Rome, in the treatises that have modified the institutive treatises –Single European Act, Treaty of Accession, Treaty of Maastricht, Treaty of Amsterdam, Treaty of Nice, Treaty of Lisbon, as well as other communal acts adopted by the European institutions - directives, decisions, regulations and so on. The European law represents a new juridical order, autonomous from the international order and in the same time integrated in the juridical system of the member states. The primary source of law is considered to be the first three institutive treatise and the treatises that brought some changes to them. Whereas, we call the derived legislation, those acts that are adopted based on the European treaties. At the beginning, the first European juridical norms were the result of the sovereign will of the member states, which, through classical international treaties, agreed to give away part of their sovereignty and started to obey the will of supranational institutions. Later on, these institutions created, by their own power, norms that are applied at a supranational level.
The European law, being, in a direct manner (treaties) or indirect (adopted acts) the creation of the member states, can be understood in the following context
It is a supranational law
It is a legislation distinct from the internal law of the member states
It is at the same time, integrated in the internal law of the member states, in the national juridical order.
European Court of Justice
It is the fourth European institution with headquarters in Luxembourg and has the mission to apply, interpret and safeguard the community law throughout the whole territory of the European Union.  The European judges cannot be influenced in their decisions by their belonging to a member state, and they must follow the community interest. The litigations brought before it are between European institutions, between European Commission and member states, between member states, or, between natural or juridical persons and the European Union. All litigations have civil or administrative nature, as the Court does not have criminal competences.
The Court is formed by 27 judges, one for each member state. It is also assisted by 8 Advocates General, the Council of the European Union having the possibility to increase their number by unanimity vote to the proposal of the Court.
The Court performs two functions
A jurisdictional function; 1. When it behaves as a constitutional court, judging the recourses against an European institution or a member state that does not fulfill its obligations from the treaties or when it interprets community acts. 2. When it behaves as an administrative court, controlling the legality of community acts and judging the recourses of community officials. 3. When it exercises the functions of civil jurisdiction, solving the cases that have as object the granting material damage. 4. When it acts as a court of appeal, judging the recourses against the decisions of the General Court (known before as the Court of First Instance).
A consultative function, as it issues notifications in the case when the revision of treatise is debated or the need to complete international accords. 
Principle of Supremacy
The Community Law is applicable with priority in national juridical order of the member states, over the internal law of them. The supremacy of the European law implies 2 things:
Through later national laws (or other normative acts) it cannot be modified or abrogated community normative dispositions, any such rule being null and inapplicable.
Later community norms modify or make inapplicable the national juridical norms. The administration and the national judges will assure the necessary correlation and will leave inapplicable, if such be the case, the internal norms contrary to the community law. 
The founding treatise are silent on the issue of priority between national and community law. The European Court of Justice (ECJ) had no hesitation in declaring that the community law must take priority over, and supersede any national provision which clashes with the community law. This was established in the case Costa vs. E.N.E.L.  Primacy, at least as asserted by the ECJ, is over both ordinary national law and national constitutional law of Member States, even when the national constitutional law refers to the protection of the human rights or to the internal structure of the member states. It follows from the principle of supremacy that a national court is bound to enforce community law and give full effect to it, if necessary refusing on its own motion to apply any conflicting provision of national legislation. When faced with a national provision which clashes with Community law, a national court should apply community law and should not wait for annulment or repeal of inconsistent national law by domestic legislatures or constitutional organs. The doctrine of supremacy necessarily limits the sovereign right of the Member States.
There is no mention of the supremacy of Community law in the founding Treaties. The absence of any express provision is not, however, a gap in the Community law but a result of diplomacy and caution. Indeed, an express provision would have confirmed the federal nature of the community and thus dissuaded some member states from acceding to the Communities. For this reason less controversial phraseology was used, for example, in article 249 EC, which confers binding effect upon measures adopted by the EC institutions, and in article 10 EC,  which requires that member states abstain from taking measures capable of compromising the attainment of the objectives of the Treaty.
The supremacy of the community law is based on the fact that, contrary to ordinary international treaties, the founding Treaties have created their own legal system. According to the ECJ the supremacy results from the peculiar nature of the community and not from concessions made by constitutional laws of the member states. For that reason, the primacy of the community law does not depend on which theory each member state applies in order to determine the relation between national and international law. From the perspective of the ECJ the supremacy of the community law is unconditional and absolute. All community law prevails upon all national law. This means that the national laws are subservient to all sources of community law. 
When it comes to the hierarchy of the community norms, they can be ordered based on an scale that does not expressively result from the treaties, but rather from the corroboration of several articles and principles of them. The hierarchy of the community law does not presuppose that there are differences in the application of them and does not institute differences in their juridical power. The constitutive treaties are at the top of the pyramid. The classification of the other juridical norms of the community cannot be done in an abstract manner and with general applicability  . Hence, for every particular situation, there has to be established, concretely, through the application of the principle of specialty (lex specialis derogate lex generalis) and/or the principle of succession in time (lex posteriori), which norm has superior juridical power. 
Principle of Direct and Immediate Applicability
The juridical norms of the community law are applied immediately in the juridical order of the member states.  In order to better understand this characteristic of the European law, we must refer to the two principles applicable to the relation between international law resulting from treaties and the internal law of the states signing the treaty the monism and dualist principles  .
According to the monist principle, between the international juridical order and the national one, there is a continuity, therefore the treaties are applied immediately and directly in the national order without the necessity of them being received through internal juridical norms. The international juridical norm will maintain this character in regard to the national juridical norms. The dualist principle, on the other hand, presupposes the distinct existence of the two juridical orders, national and international, and requires the taking/adoption of the international treaty in the national juridical norms so as to be applied at the national level. The treaty becomes, consequently, internal law , having the same juridical power, it is “nationalized" and in this respect will be applied by the national institutions.
At the level of the European Union, the monist principle has been preferred,  because the other solution would have affected the European integration due to the fact that the European law would have had different juridical force from country to country, depending upon the juridical instrument through which it was adopted. Consecrated therefore in the community treaties  , the monist principle was recognized by the European Court of Justice, in the already famous Decision 6/64, Costa vs. E.N.E.L. “It follows from all these observations that the law stemming from the treaty, an independent source of law, could not, because of its special and original nature, be overridden by domestic legal provisions, however framed, without being deprived of its character as community law and without the legal basis of the community itself being called into question."
In conclusion, the community law is directly applicable in the juridical order of the member states immediately after its adoption, more precisely published in the Official Journal of The European Union. The Direct applicability of the community law implies two aspects:
Once adopted at the community level, the norms apply directly and immediately in the national juridical order of the member states without them being taken into internal juridical norms. Moreover, as the Court of Justice specifies, it is strictly forbidden that they are taken into internal laws.
Direct applicability determines the direct effect of the European law, hence the possibility to institute rights and obligations  to all the subject of the community juridical order not just for the member states. In theory, the international treaties can’t create rights and obligations directly for the benefit of natural or legal persons from the member state, but only to the states as such, they being the only subjects of classic international law. However, this concept has been dented by the creation of European Court of Human Rights, in which, the issues of individuals from the member states can be addressed. So, in this case the member states have agreed upon, by the signature of the institutive treaties, giving right and obligations directly to individuals. 
Principle of subsidiarity
The small democratic legitimacy of the European institutions and their more expanded rights in the adoption of legislation applicable to member states, had lead to the adoption in the community law of the principle of subsidiary,  meant to bring a sense of security to the Europeans beginning to fear the “bureaucracy in Brussels". The principle of subsidiary governs the repartition of competences between the Union and the member states.
The treaty on European Union (Maastricht) and to a lesser extent the Single European Act formalize a subsidiarity principle. This much debated principle holds that the union can act in areas where it does not exclusively have power only if the member states cannot sufficiently achieve the objectives i.e. “by reason of scale or effects [the] proposed action [can] be better achieved by the community."In all cases, the European Union action must go beyond what is necessary to achieve the objectives of the Treaty of Rome (proportionality principle). Thus subsidiarity is a kind of “states’ rights" amendment intended to limit the growth of regional government in Europe. An international agreement by the Council, Commission, and European Parliament on the application of the subsidiarity principles by all EU institutions has been negotiated. Subsidiarity guidelines were adopted by the European Council in December of 1992 
There are two concepts characterizing the community law: subsidiarity and proportionality. Whilst subsidiarity refers to the subject called to complete certain objectives, proportionality refers to the intensity of the action with regard to the necessity of the objective. Consequently, the principle of proportionality has as a goal the “quantitative" limitation of the community action to what is strictly necessary. The subsidiarity is being discussed only in the cases of shared competences of the Union and member states and not in the case where the competences belong to the Union exclusively. The tendency to regulate everything in Brussels has numerous explanations and can’t be stopped easily. Thus, the European integration presupposes the uniform regulation of sensible fields such as trade, agriculture, industry, in order to ensure o fair competition within the community. There rest in the exclusive competence of the member states fields such as services of public health, culture, education. We can identify the desire of the European Commission to transform itself in a fully-fledged European government and the frustration of the European Parliament that it is not a genuine parliament;
Limitation to the community law
It has always been clear that there are limits to the scope and field of application of EU law. This goes to the heart of the legitimacy of the EU project. The question is what are those limits and where do the outer limits actually lie?Even in a single state identifying the limits of public power can be a difficult exercise. A federal system adds the complexity of knowing which part of the public sphere is properly authorised to exercise that power, and identifying the limits imposed in the division of competence between the central and local levels. For example, in one period criminal law matters or national security appear to fall wholly outside the scope of EC law and go to the core of national sovereignty; gradually Community law begins to encroach even upon these fields. In the context of the EU, it has long been known that the Union is not a self-authenticating entity. Instead, the EU is limited to exercising the powers conferred upon it by the Member States. This is made clear at a formal level in Article 5(1) EC, which provides that ‘[t]he Community shall act within the limits of the powers conferred upon it by this Treaty and of the objectives assigned to it therein’. This attempt to define the limits of the Community’s competence creates the presumption that all which is not conferred remains with the Member States. The Lisbon Treaty makes this point expressly: Article 4(1) TEU-L provides that in accordance withArticle 5, competences not conferred upon the Union in the Treaties remain with the Member States. Article 5(1) TEU-L states ‘The limits of Union competences are governed by the principle of conferral’. ‘Conferral’ is defined in Article 5(2) TEU-L as the Union acting ‘only within the limits of the competences conferred upon it by the Member States in the Treaties to attain the objectives set out therein’. For good measure it adds ‘Competences not conferred upon the Union in the Treaties remain with the Member States’. 
So far we have concentrated on the most obvious and visible limit to the Community’s competence: its capacity to legislate in defined areas only. This means that, in principle, all other areas are left to the Member States. But this is not the only way that the Treaty creates space for Member States to act. Another obvious example is the derogations from the four freedoms (such as public policy, public security and public health). However, a study of cases decided in 1984, 1994 and 2004 reveals that increasingly the Court is saying that, on the facts of a particular case, the Member State has failed to make out a justification or, if it has made out a justification, the steps taken do not comply with the principles of proportionality, fundamental rights, effective judicial protection and legal certainty. This has marked a significantshift in the balance of power between the EU and the Member States.
While it is clear that there are limits to EU law, there is also evidence that the Community and the Union stray beyond those limits  . Eurosceptics cry foul. Europhiles are more benign: they recognise that the EU must stay within the limits laid down as part of the process of legitimising the endeavour but they also realise that the EU’s legitimacy is under threat if it fails to deliver. Thus the EU must be able to function effectively and, at times, this requires a generous interpretation of rules which are themselves open textured. 
We can still say that there are things that the EU does not do and ought not do: it does not have a police force or an army, it does not provide social welfare, education or health care. Nor does the EU have the competence to do any of these things. However the EU, and the Court in particular, is prepared to control the exercise of these powers by the Member States where national rules affect free movement. As the health care cases demonstrate, this inevitably has an impact on the shape of provision by the national systems. It is in this context that some of the allegations of competence creep are most pronounced. And it is here that the EU must tread most carefully since the legitimacy of the EU is at its most precarious.
According to Romanian Constitution an international treaty is a source of constitutional law if it accomplishes the following conditions: it is licit; its application is direct, immediate; the treaty must be ratified according to the international norms; it must contain provisions of constitutional law. The Romanian State pledges to fulfill as such and in good faith its obligations as deriving from the treaties it is a party to  ; Only the treaties  ratified by the Parliament, according to the law  are part of the national law; Under Romanian Law, ratification of a treaty in accordance with the procedure for which the constitution provides, followed by its publication in the Official Journal is sufficient to incorporate it into domestic law, whereby giving it the force of positive law. In practice, the self-executing method is applied whenever possible. Otherwise, domestic law has to be amended to make it compatible with the international law concerned. 
The essential feature that community law enjoys in comparison with general international law is its specific direct effect nature, meaning that it enjoys supremacy, direct applicability and by itself and not because the national constitution or the national law provides so. Thus, the accession of new member states assumed ab initio the transfer to the Union of powers of state sovereignty, and thereafter the common exercise of some powers that traditionally fall within the scope of state sovereign power. 
Institutional guarantees provided by Romanian constitution endorse all the three branches of government: legislative, executive and judiciary to the extent that the integration to EU assumes their participation to the observance and the enforcement of community norms, within the limits of their constitutional powers. Thus, in the context of the European integration the need for rethinking the concept of sovereignty flourished, new concepts emerging like: open statehood, post-sovereignty, late-sovereignty, multilevel governance.
Starting from the rethinking of this concept, all the constitutions of the members’ states should contain provisions regarding: the delegation of competencies to the EU; the exercise of the sovereignty at national and European level as well, the latter through the European Parliament; the relation and the interaction between national and European law.
The Romanian Constitutional Court stated that, through the transfer of the competencies to the EU institutions, these do not acquire a supra-competence, their own sovereignty. In fact, the member states decided to exercise in common some competencies that traditionally are by the domain of national sovereignty. The transfer of the member states national competencies to the supranational level is not possible without a democratic control of the citizens of the member states, realized through the European Parliament.
Prior to the revision in 2003, Romanian Constitution did not contain provisions concerning the transfer of state powers to international organizations or the joint exercise with other states of competencies specific to state sovereignty. It only contained the general rules of article 11 and 20  , developed in the second chapter of the paper. After the revision, article 148  regulates an exception from the rule, applied only to the European integration, article which provides special rules for the accession to EU. According to this article, Romania’s accession to the constituent treaties of the European Union, with a view to transferring certain powers to community institutions, as well as to exercising in common with the other member states the competencies stipulated in such treaties, shall be carried out by means of a law adopted in the joint session of the Chamber of Deputies and the Senate, with a majority of two thirds of the number of Deputies and Senators.
The law of ratification of Romania’s accession is an atypical law in the Romanian legal system, irrespective of the formal or material aspects. Regarding the material aspect, this is a law of ratification of international treaties. It is neither a law of the revision of the Constitution because it does not modify the fundamental law, nor an organic or ordinary law, the transfer of the competencies to the European institutions or the exercising of powers in common with other member states prevailing over the domain of ordinary and organic laws. Concerning the formal aspect, this law is approved with a majority of two thirds of the number of Deputies and Senators, which is different from the majority of two thirds of the number of deputies and senators, taken separately required for the revision of the constitution on a first phase. 
Article 148 par. 4 and 5 provides institutional guarantees for all the three branches of government regarding transposition into national law of the community law through primary or secondary acts and the real enforcement of this legislation through administrative and judiciary bodies. This provision of the Romanian constitution is in accordance with the general norms of public international law, ECJ establishing a wide jurisprudence  concerning the state liability for breaches or infringement of community law, irrespective of the facts are of legislative, judiciary or administrative bodies. The next paragraph establishes constitutional rules for well functioning of state institutions within European institutions. Thus the executive branch, the Government shall send to the two Chambers of the Parliament the draft mandatory acts before they are submitted to the European Union institutions for approval.
Concerning the state liability for breaches or infringement of community law, irrespective of the facts are of legislative, judiciary or administrative bodies. The next paragraph establishes constitutional rules for well functioning of state institutions within European institutions. Thus the executive branch, the Government shall send to the two Chambers of the Parliament the draft mandatory acts before they are submitted to the European Union institutions for approval.
Article 148 par. 1 of the Romanian Constitution provides the priority of the community law over the national one and par. 2 adds that this is an original priority because only the constitutive treaties and other mandatory community regulations have priority over the internal contrary provisions. Irrespective of the words used by the Romanian derivative constituent power, the enforcement of the principle of priority is the task of all Romanian authorities involved in the process of compliance of Romanian legislation with the European norms.  The Romanian constitutional court in the decision 148/2003 concluded that community norms have supra-legislative but infra-constitutional force, thus acquis communautaire having an intermediary position between constitution and other laws, when speaking of mandatory European legal norms.
Regarding the conflict between national law and European law, the same court in the decision no. 558/2007  , concluded that national courts should address to the European Court of Justice in order to assure the effective and homogeneous enforcement of the community law. In a relatively new decision, the Court said that the aspects concerning the compatibility of internal provisions with community law do not represent issues of constitutionality, being aspects of enforcement of legislation by the judicial courts, superseding the competence of the Constitutional Court.
Romanian judges expressed their position also regarding the relation between national law and community law, for example in the decision no. 4403/31.05.2007, the High Court of Cassation and Justice concluded that the community law has priority over the contrary internal law, producing concrete effects within the national order, the national judge being obliged to sanctionate the contrary. In other decision no. 2620/23.03.2007, the High Court stated that if the internal norms are in contradiction with community norms, the later have priority in accordance with the principles of priority and direct effect of the community law.
Thus, given the special character of EU, some features of federal arrangements can be find, features which had been taken into consideration by the Romanian constitutional power: the limitation of national sovereignty in favour of the EU; three levels of competencies: some competencies are given exclusively to the EU, others are shared with member states and others resting to the member states; recognition of the principle of subsidiarity which allows national parliament to signal a particular decision does not comply with the principle.
Going beyond this point, there remain the judges, who alone, with the instruments available to them (legislation, case law, legal theory, domestic and international law) and with their desire to learn about, familiarize themselves with, and develop these, are responsible for the dispensation of justice, and ultimately for applying the law, taking appropriate action in each individual case under the general provisions.