Adolf Hitler and Hermann Göring arrived soon after, and when they were shown van der Lubbe, a known communist agitator, Göring immediately declared that the fire was set by the communists and had the party leaders arrested. Hitler took advantage of the situation to declare a state of emergency and encouraged the aging president Paul von Hindenburg to sign the Reichstag Fire Decree, abolishing most of the human rights provided for by the 1919 constitution of the Weimar Republic.
According to the police, van der Lubbe claimed to have set the fire as a protest against the rising power of the Nazis. Under torture, he confessed again, and was brought to trial, along with the leaders of the opposition Communist Party. With their leaders in jail and denied access to the press, the Communists were badly defeated in the next election and those Communist (and some Social Democratic) deputies that were elected to the Reichstag were not permitted by the SA to take their seats. Hitler was swept to power with 44 percent of the vote and coerced the remaining minor parties to give him the two-thirds majority for his Enabling Act which gave him the right to rule by decree and suspended many civil liberties.
At his trial, van der Lubbe was found guilty and sentenced to death. He was beheaded on July 10, 1934, three days before his twenty-fifth birthday.
On the other hand, in one of the last twitches of a constitutional state, the Reichsgericht court acquitted the communist party leadership. This infuriated Hitler, who decreed that henceforth treason -- among many other offenses -- would only be tried by a newly established Volksgerichtshof ("People's Court"), which became infamous for the enormous number of death sentences that it imposed under the later lead of Roland Freisler.
Historians generally agree that van der Lubbe, sometimes described as a half-wit, was somehow involved in the Reichstag fire. The extent of the damage, however, has led to considerable debate over whether he acted alone. At the trial the communists were acquitted, making it difficult to believe that they were actually involved. Considering the speed with which the fire engulfed the building, van der Lubbe's reputation as a fool hungry for fame, and cryptic comments by leading Nazi officials, it is generally believed that the Nazi hierarchy was involved in order to reap political gain -- and it obviously did. Nevertheless, there is no conclusive evidence either way.