Tax obligations secured by mortgages shall not be subject to limitation. Tax creditor, who was secured by a compulsory mortgage, may satisfy his claim much later than a private creditor. The authors point out that this type of security put the people in a privileged situation who do not have the assets on which the establishment of a compulsory mortgage is possible. Moreover, the tax authorities may arbitrarily decide on whose property will be established a mortgage. All these facts show that the provisions on compulsory mortgage violate the constitutional principle of equality before the law.