The concept of a 'Welfare State' signifies a government that actively intervenes in the social and economic well-being of its citizens through various programs and regulations, such as social security, public health, education, housing, and economic regulation. This expansive role of the state led to a significant increase in administrative functions, which in turn necessitated the development of 'Administrative Law' to govern and control these governmental activities. The growth of administrative law, in turn, made 'Administrative Tribunals' an indispensable component of the justice delivery system.

Development of Administrative Law in a Welfare State:

1. Increased State Functions: As the state transitioned from a 'police state' to a 'welfare state,' its functions multiplied exponentially. It became a provider, regulator, and dispenser of services, leading to a vast increase in administrative decisions affecting individuals and organizations.
2. Delegated Legislation: Parliament, unable to legislate on every minute detail of complex welfare programs, delegated significant rule-making powers to administrative bodies. Administrative law emerged to ensure that these delegated powers were exercised within legal limits and not arbitrarily.
3. Discretionary Powers: Administrators were granted wide discretionary powers to implement policies effectively. Administrative law developed to provide a framework for the exercise of this discretion, ensuring fairness, reasonableness, and adherence to the principles of natural justice.
4. Need for Control: The potential for abuse of power, inefficiency, or arbitrary decisions by a burgeoning bureaucracy necessitated a specialized body of law to control administrative actions and protect citizens' rights.

Necessity of Administrative Tribunals due to Administrative Law Development:

The traditional judicial system (ordinary courts) proved inadequate to handle the sheer volume and specialized nature of disputes arising from the expanded administrative functions and the complexities of administrative law. This inadequacy made administrative tribunals a necessity for several reasons:

1. Burden on Ordinary Courts: The massive increase in administrative actions and the corresponding rise in disputes would have overwhelmed the already burdened ordinary courts, leading to severe delays in justice delivery.
2. Specialized Expertise: Administrative law often deals with highly technical and specialized areas (e.g., tax, environmental regulations, service matters, intellectual property). Ordinary judges, being generalists, might lack the specific expertise required to adjudicate these complex cases effectively. Tribunals, staffed by experts in relevant fields, offer specialized knowledge.
3. Speed and Cost-Effectiveness: Traditional court procedures are often lengthy, formal, and expensive. Administrative tribunals are designed to be quicker, less formal, and more cost-effective, providing faster redressal to citizens, which is crucial for the effective implementation of welfare policies where timely decisions are vital.
4. Flexibility and Informality: Tribunals are less bound by strict rules of evidence and procedure, allowing for a more flexible and pragmatic approach to justice, focusing on the substance of the dispute rather than procedural technicalities.
5. Focus on Public Interest: While safeguarding individual rights, tribunals can also consider the broader public interest and policy objectives, which might be a secondary consideration for traditional courts focused solely on legal rights.
6. Accessibility: Tribunals are often designed to be more accessible to the common person, reducing geographical and financial barriers to justice, thereby promoting social justice.
7. Effective Review of Discretion: A core tenet of administrative law is the review of administrative discretion. Tribunals provide an effective mechanism for this review, ensuring that discretionary powers are exercised fairly, reasonably, and within the bounds of the law.

In conclusion, the evolution of the welfare state led to an unprecedented expansion of governmental functions and, consequently, the development of administrative law to regulate this power. This growth, in turn, created an imperative for specialized, efficient, and accessible dispute resolution mechanisms. Administrative tribunals emerged as a practical and essential response, complementing the traditional judiciary by providing expert, speedy, and cost-effective justice in the administrative realm, thereby upholding the rule of law and ensuring accountability in the welfare state.