While the State thus for years dealt very leniently with the railroad companies, the laws of Iowa had from the beginning of railroad building emphasized the principle of State control. This principle was asserted in the very first railroad act ever passed in the State. Section 14 of chapter I. of the acts of the extra session of the Fifth General Assembly, regranting to the various railroad companies the lands granted to the State by Congress for railroad purposes, provides that "railroad companies accepting the provisions of this act shall at all times be subject to such rules and regulations as may from time to time be enacted and provided for by the General Assembly of Iowa...." In 1866 an attempt was made in the General Assembly to regulate rates, but the Attorney-General, to whom the question of constitutionality was submitted, held in his opinion that it was not in the power of the legislature to prescribe rates for railroad companies. This opinion provoked much indignation among the people of the State, and led to the expression of a sound public opinion by legislative acts which could not be misunderstood. When the Twelfth General Assembly (in 1868) regranted to the Chicago, Rock Island and Pacific Railroad Company the lands originally granted to the Mississippi and Missouri Company, it only did so upon the condition that "said railroad company, accepting the provisions of this act, shall at all times be subject to such rules, regulations and rates of tariff for transportation of freight and passengers as may from time to time be enacted and provided for by the General Assembly of the State of Iowa...." The same restricting clause, known as the Doud Amendment, was added to all other land grant acts passed by the Twelfth and subsequent General Assemblies, and the various companies willingly and gladly accepted it.