Today, one of the most pressing and controversial issues is the search for an optimal balance between the duty of citizens to pay taxes and the fair tax burden.

The purpose of this article is to highlight the doctrinal and practical issues which may arise when the constitutional complaint mechanism is applied for the protection of tax relations, and to develop conceptual proposals for resolving these issues.

Today it is acknowledged that one of the major features of modern constitutions is such a property thereof as horizontal effect. It is therefore not without reason that under Art. 3.1. of the Tax Code of Ukraine the Constitution of Ukraine is a constituent part of Ukraine’s tax legislation. Having analyzed the nature and essence of the principles underlying the tax legislation, we believe that the ultimate goal of these principles is to ensure respect for human dignity. And it is particularly through the prism of human dignity that constitutional complaints should be considered in the constitutional proceedings. We should separately note such an issue as the substantive dimension of the right to dignity in the context of economic and social rights which are closely linked to the taxation issue. The right to respect for dignity is at the same time the basic axiological parameter which has no absolute content (i.e., its particular content should be established in each case of exercise of the right), determines the essence of actions of public authority and the subjects of economic and social relations, and forms the foundation for determining the scope of potential restrictions on the exercise of constitutional rights and freedoms of man and citizen.

The full-fledged democratic activity would be impossible without creating the mechanisms to facilitate communication and serve as a bridge of the dialogue between civil society and the State. When dealing with such a category of cases as tax complaints, it is of particular importance how society perceives the decisions made based on the results thereof.

Today, introduction of the institute of constitutional complaint is a significant achievement for the system of protection of constitutional rights and freedoms of man and citizen in Ukraine. And the Constitutional Court of Ukraine is facing a challenge of working out the practice of constitutional complaints consideration based on modern conceptual approaches and principles established in democratic countries.

List of legal documents 
Legislation 
1. Constitución Política de los Estados Unidos Mexicanos 1917, con cambios en 2012 accessed 8 February 2018 (in Spanish). 
2. Konstytutsiia Ukrainy [Constitution of Ukraine]: Zakon Ukrainy [the Law of Ukraine] vid 28 chervnia 1996 r. № 254k/96-VR, zi zminamy. URL: http://zakon3.rada.gov.ua/ laws/show/254k/96-vr (accessed: 06.05.2018) (in Ukrainian). 
3. Podatkovyi kodeks Ukrainy [Tax Code of Ukraine]: Zakon Ukrainy [the Law of Ukraine] vid 2 hrudnia 2010 r. № 2755-VI. URL: http://zakon5.rada.gov.ua/laws/ show/2755-17 (accessed: 06.05.2018) (in Ukrainian). 
4. Pro Konstytutsiinyi Sud Ukrainy [On the Constitutional Court of Ukraine]: Zakon Ukrainy [the Law of Ukraine] vid 13 lypnia 2017 r. № 2136-VIII. URL: https://zakon. rada.gov.ua/laws/show/2136-19 (accessed: 12.12.2018) (in Ukrainian). 
5. Rehlament Konstytutsiinoho Sudu Ukrainy, zatverdzhenyi postanovoiu Konstytutsiinoho Sudu Ukrainy [Rules of the Constitutional Court of Ukraine, Аpproved by the Вecision of the Constitutional Court of Ukraine] vid 22 liutoho 2018 r. URL: www.ccu. gov.ua/docs/177 (accessed: 08.05.2018) (in Ukrainian). 

Cases 
6. Rishennia Konstytutsiinoho Sudu Ukrainy u spravi za konstytutsiinym podanniam 53 narodnykh deputativ Ukrainy shchodo vidpovidnosti Konstytutsii Ukrainy (konstytutsiinosti) okremykh polozhen Podatkovoho kodeksu Ukrainy [Decision of the Constitutional Court of Ukraine in the Case Following the Constitutional Submission of 53 People’s Deputies of Ukraine Concerning the Compliance with the Constitution of Ukraine (Constitutionality) of Some Provisions of the Tax Code of Ukraine] vid 12 chervnia 2012 r. № 13-rp/2012. URL: http://zakon5.rada.gov.ua/laws/show/ v013p710-12 (accessed: 08.05.2018) (in Ukrainian). 
7. Rishennia Konstytutsiinoho Sudu Ukrainy u spravi za konstytutsiinym podanniam 48 narodnykh deputativ Ukrainy shchodo vidpovidnosti Konstytutsii Ukrainy (konstytutsiinosti) polozhen punktu 1.17 statti 1, statti 8 Zakonu Ukrainy “Pro poriadok pohashennia zoboviazan platnykiv podatkiv pered biudzhetamy ta derzhavnymy tsilovymy fondamy” (sprava pro podatkovu zastavu) [Decision of the Constitutional Court of Ukraine in the Case Following the Constitutional Submission of 48 People’s Deputies of Ukraine Concerning the Compliance with the Constitution of Ukraine (Constitutionality) of the Provisions of Cl. 1.17, Article 1, Article 8 of the Law of Ukraine “On the Procedure for Repayment of Taxpayers Obligations to Budgets and State Target Funds” (Case of Tax Pledge)] vid 24 bereznia 2005 r. № 2-rp/2005. URL: http://zakon2. rada.gov.ua/laws/show/v002p710-05 (accessed: 08.05.2018) (in Ukrainian). 
8. Rishennia Konstytutsiinoho Sudu Ukrainy u spravi za konstytutsiinym podanniam 57 narodnykh deputativ Ukrainy shchodo vidpovidnosti Konstytutsii Ukrainy (konstytutsiinosti) Zakonu Ukrainy “Pro vseukrainskyi referendum” [Decision of the Constitutional Court of Ukraine in the Case Following the Constitutional Submission of 57 People’s Deputies of Ukraine Concerning the Compliance with the Constitution of Ukraine (Constitutionality) of the Law of Ukraine “On the All-Ukrainian Referendum”] vid 26 kvitnia 2018 r. № 4-r/2018. URL: http://zakon0.rada.gov.ua/laws/ show/v004p710-18 (accessed: 03.03.2018) (in Ukrainian). 
9. Rishennia Konstytutsiinoho Sudu Ukrainy u spravi za konstytutsiinym podanniam 57 narodnykh deputativ Ukrainy shchodo vidpovidnosti Konstytutsii Ukrainy (konstytutsiinosti) Zakonu Ukrainy “Pro zasady derzhavnoi movnoi polityky” [Decision of the Constitutional Court of Ukraine in the Case Following the Constitutional Submission of 57 People’s Deputies of Ukraine Concerning the Compliance with the Constitution of Ukraine (Constitutionality) of the Law of Ukraine “On the Foundations of the State Language Policy”] vid 28 liutoho 2018 r. 
№ 2-r/2018. URL: http://zakon0.rada.gov.ua/laws/show/v002p710-18 (accessed: 
03.03.2018) (in Ukrainian). 
10. Rishennia Konstytutsiinoho Sudu Ukrainy u spravi za konstytutsiinym podanniam Prezydenta Ukrainy shchodo vidpovidnosti Konstytutsii Ukrainy (konstytutsiinosti) Zakonu Ukrainy “Pro vnesennia zmin do deiakykh zakonodavchykh aktiv Ukrainy” (sprava pro podatky) [Decision of the Constitutional Court of Ukraine in the Case Following the Constitutional Submission of the President of Ukraine Concerning the Compliance with the Constitution of Ukraine (Constitutionality) of the Law of Ukraine “On Amendments to Some Legislative Acts of Ukraine” (Case of Taxes)] vid 5 kvitnia 2001 r. № 3-rp/2001. URL: http://zakon5.rada.gov.ua/laws/show/v003p710-01 (accessed: 08.05.2018) (in Ukrainian). 

Bibliography 
Authored books 
11. Néstor P Sagües, Manual de derecho constitucional (Editorial Astrea edn. 2007) accessed 8 February 2018. 
12. Hultai M, Konstytutsiina skarha u mekhanizmi dostupu do konstytutsiinoho pravosuddia [Constitutional Complaint in the Mechanism of Access to Constitutional Justice] (Pravo 2013). 
13. Kyrychenko Yu ta Bondarenko B, Analitychnyi zvit shchodo zaprovadzhennia instytutu konstytutsiinoi skarhy [Analytical Report on the Introduction of the Institute of Constitutional Complaint] (FOP Moskalenko O. M. 2018) accessed 3 March 2018 (in Ukrainian). 

Dictionaries 
14. Savchyn M, ‘Horyzontalnyi efekt konstytutsii’ [‘Horizontal Effect of the Constitution’] v Boshytskyi Yu (za zah red), Mala entsyklopediia konstytutsiinoho prava [Small Encyclopedia of Constitutional Law] (Kondor-Vydavnytstvo 2012) (in Ukrainian). 

Journal articles 
15. Adrián Alfonso Paredes Santana, ‘Debe desaparecer el juicio de amparo contra impuestos?’ (2015) 2 Boletín fiscal accessed 15 February 2018 (in Spanish). 
16. Antonio M. García Cuadrado, ‘Problemas constitucionales de la dignidad de la persona’ (2012) 67 Persona y Derecho 504 accessed 8 May 2018 (in Spanish). 
17. Bauer F. Bronstrup, ‘El amicus curiae en la jurisdicción constitucional española’ (2016) 108 Revista Española de Derecho Constitucional 184 accessed 8 May 2018 (in Spanish). 
18. César Landa, ‘Dignidad de la persona humana’ (2002) 7 Cuestiones constitucionales 130 accessed 8 May 2018 (in Spanish). 
19. Ingo von Munch, ‘La dignidad del hombre en el derecho constitucional’ (1982) 5 Revista Española de Derecho Constitucional 18 accessed 8 May 2018 (in Spanish). 
20. Simón Yarza Fernando, ‘Reseña biblográfica “Schmitt, Carl: La tiranía de los valores, Comares, Granada’ (2010) 90 Revista Española de Derecho Constitucional 389 accessed 8 May 2018 (in Spanish). 

Newspaper articles 
21. Vdovychenko S i Kampo V, ‘Hidnist liudyny: aspekty zakhystu’ [‘Human Dignity: Aspects of Protection’] (2012) 142 Holos Ukrainy 6 (in Ukrainian). 

Dissertations 
22. Airiian K, ‘Konstytutsiina skarha yak forma zvernennia do orhanu konstytutsiinoi yurysdyktsii’ [‘Constitutional Complaint as a Form of Application to the Constitutional Jurisdiction Body’] (dys kand yuryd nauk, Natsionalna akademiia vnutrishnikh sprav 2015) (in Ukrainian). 
23. Bryn T, ‘Konstytutsiinyi Sud Ukrainy v mekhanizmi zakhystu ta zabezpechennia prav i svobod liudyny i hromadianyna’ [‘Constitutional Court of Ukraine in the Mechanism of Protection and Ensuring of Human and Citizen’s Rights and Freedoms’] (dys kand yuryd nauk, Natsionalna yurydychna akademiia im. Yaroslava Mudroho 2010) (in Ukrainian). 
24. Holovin A, ‘Zakhyst prav i svobod liudyny i hromadianyna yedynym orhanom konstytutsiinoi yurysdyktsii v Ukraini’ [‘Protection of Human and Citizen’s Rights and Freedoms by a Single Constitutional Jurisdiction Body in Ukraine’] (dys kand yuryd nauk, Natsionalna akademiia vnutrishnikh sprav 2013) (in Ukrainian). 
25. Kravchenko O, ‘Zakhyst prav i svobod liudyny ta hromadianyna Konstytutsiinym Sudom Ukrainy: doktrynalni, prykladni ta komparatyvni aspekty’ [‘Protection of Human and Citizen’s Rights and Freedoms by the Constitutional Court of Ukraine: Doctrinal, Applied and Comparative Aspects’] (dys kand yuryd nauk, Instytut zakonodavstva Verkhovnoi Rady Ukrainy 2011) (in Ukrainian). 
26. Kryzhanovskyi V, ‘Konstytutsiino-pravovi zasady sudovoho zakhystu prav i svobod liudyny i hromadianyna v Ukraini’ [‘Constitutional Law Foundations of Court Protection of Human and Citizen’s Rights and Freedoms in Ukraine’] (dys kand yuryd nauk, Natsionalnyi universytet “Odeska yurydychna akademiia” 2013) (in Ukrainian). 
27. Tkachuk A, ‘Konstytutsiinyi sud u mekhanizmi zakhystu osnovnykh prav i svobod liudyny: modelnyi pidkhid’ [‘Constitutional Court in the Mechanism of Protection of Fundamental Human Rights and Freedoms: a Model Approach’] (dys kand yuryd nauk, Instytut zakonodavstva Verkhovnoi Rady Ukrainy 2012) (in Ukrainian).