Weimar Republic's new constitution was adopted in August 1919. Many historians put the blame for Weimar's future political problems on this constitution in that, ironically, it was too fair as it included everybody regardless of their political beliefs. However, Ebert was committed to democracy and the new constitution had his full support.
The constitution introduced a bi-cameral assembly: this was a parliament that was made up of two layers; one represented the whole nation (the Reichstag) and made whole-nation decisions while the other represented regions (the Reichsrat).
The Reichstag was made up of politicians who were elected through universal suffrage. All people over 20 years of age could vote. Politicians of the Reichstag sat for four years and then they had to stand for re-election. The Reichstag used a system of proportional representation for elections. Issues such as finance, tax, foreign policy etc. were discussed.
The Reichsrat represented regional governments within Germany such as Prussia, Bavaria and Saxony. Their task was limited to examining regional issues.
The president was the head of state. He was elected for a term of seven years.
The president could appoint his chancellor with the recommendation that the Chancellor should have the support of a majority in the Reichstag.
He was also in theory the head of the armed forces.
The president could also dissolve the Reichstag and call a general election if he felt the political situation warranted it.
He could also veto (refuse to support) Reichstag legislation (laws passed by the Reichstag). By doing this, the president could kill off any Reichstag laws he disapproved of.
The president could also declare a state of emergency and rule by emergency decree.
The constitution was genuinely democratic, after the sham democracy of Kaiser William II.
Elections were built around universal suffrage and proportional representation. However, the theoretical strength of the constitution was also its Achilles heel. Everybody was allowed to vote including extremists from both sides of the political spectrum - left and right. The system of proportional representation also meant that if any minor party got the necessary votes, they would have party members in the Reichstag. The major parties would continue to dominate the Reichstag, but the minor parties could disrupt proceedings and make the party in power - the Social Democrats - look incapable of maintaining order in its very seat of power. This is exactly what the new Nazi Party did in its early years. It got enough votes to get a few members into the Reichstag (as a result of proportional representation) and those Nazis elected then did what they could to 'prove' to the German people that Ebert and the Social Democrats were incompetent in dealing with such basics as maintaining discipline within the Reichstag.
The constitution was to play a major part in the years 1930 -1933 when the president, Hindenburg, appointed and sacked chancellors seemingly at will.