The responsibility for the Reichstag fire remains a topic of debate and research, as while Van der Lubbe was found guilty, it is unclear whether he acted alone.

[4][5] In 2008, Germany posthumously pardoned Van der Lubbe under a law introduced in 1998 to lift unjust verdicts dating from the Nazi era.

Despite the fact that Marinus van der Lubbe claimed to have acted alone in the Reichstag fire, Hitler, after having obtained his emergency powers, announced that it was the start of a wider communist effort to take over Germany.

[20] The Nazis thought that this would make it difficult to achieve their next goal, passage of the Enabling Act giving Hitler the right to rule by decree, which required a two-thirds majority.

[22] In July 1933, Marinus van der Lubbe, Ernst Torgler, Georgi Dimitrov, Blagoi Popov, and Vasil Tanev were indicted on charges of setting the fire.

[28] The atmosphere of the opening of the trial was described by Otto D. Tolischus for The New York Times: Repeatedly during the session glaring movie picture flares illuminated the somber court room.

When warned by Judge Bünger to behave himself in court, Dimitrov stated: "Herr President, if you were a man as innocent as myself and you had passed seven months in prison, five of them in chains night and day, you would understand it if one perhaps becomes a little strained."

During the course of his defence, Dimitrov claimed that the organizers of the fire were senior members of the Nazi Party and frequently verbally clashed with Göring at the trial.

Dimitrov: Is the Reichsminister aware of the fact that those that possess this alleged criminal mentality today control the destiny of a sixth part of the world – the Soviet Union?

[25] The People's Court later became associated with the number of death sentences it handed down, including those following the 1944 attempt to assassinate Hitler, which were presided over by then Judge-President Roland Freisler.

In 1981, a West German court posthumously overturned Van der Lubbe's 1933 conviction and found him not guilty by reason of insanity.

In early historical summations, such as William Shirer's account, the Reichstag Fire is understood and represented as a conspiratorial operation carried out by Nazi storm troopers in which Van der Lubbe played the role of the patsy.

From 2014 to the present the resurfacing of a 1955 affidavit given by a stormtrooper, who testified that the building was already on fire when Van der Lubbe was delivered there by SA members, supported new scholarship re-examining the subject.

[40][41] In the days following the incident, major newspapers in the US and London had immediately been skeptical of the good fortune of the Nazis in finding a communist scapegoat.

[42][43] In 2007, it has been alleged that the idea that Van der Lubbe was a "half-wit" or "mentally disturbed" was propaganda spread by the Dutch Communist Party, to distance itself from an insurrectionist antifascist, who had once been a member.

[44] John Gunther, who covered the trial, described Van der Lubbe as "an obvious victim of manic-depressive psychosis" and said that the Nazis would not have chosen "an agent so inept and witless".

Citing a letter that was allegedly written by Karl Ernst before his death during the Night of Long Knives, Gunther believed that Nazis, who heard Van der Lubbe boast of planning to attack the Reichstag, started a second simultaneous fire they blamed on him.

Delmer viewed Van der Lubbe as being solely responsible, but that the Nazis sought to make it appear to be a "communist gang" that set the fire.

On the other hand, the communists sought to make it appear that Van der Lubbe was working for the Nazis, so each side constructed a conspiracy theory in which the other was the villain.

Tobias established that Van der Lubbe had committed a number of arson attacks on buildings in the days prior to 27 February.

Tobias undertook his study when tasked to defend West German police officials, who had investigated the initial fire as SS members.

Furthermore, Hett showed that Tobias used his access to secret archives to coerce historians with opposing views by threatening to reveal compromising personal information.

[41] More recently in 2019, mainstream German outlet Deutsche Welle (DW) reported that according to an SA officer's sworn testimony, Van Der Lubbe could not have started the fire because the Reichstag was already on fire when he arrived with Van Der Lubbe, lending credence to the theory that this was a false flag operation Hitler used to seize power.

[37] In July 2019, more than 80 years after the event, Germany's Hannoversche Allgemeine Zeitung and the RedaktionsNetzwerk Deutschland published a 1955 affidavit, uncovered in some papers of Fritz Tobias, which were found in the archives of the Amtsgericht (court) in Hannover.

[58] It also led to more sober speculation about whether unknown or forgotten documents might still be hidden in German archives, and which might be valuable and revealing historical sources, especially on the Nazi regime.

[61]: 433 During the summer of 1933, a mock countertrial was organised in London by a group of lawyers, democrats and other anti-Nazis under the aegis of German communist émigrés.

The other "judges" were Piet Vermeylen of Belgium, George Branting of Sweden, Vincent de Moro-Giafferi and Gaston Bergery of France, Betsy Bakker-Nort, a lawyer and member of parliament of the Netherlands for the progressive liberal party Free-thinking Democratic League, Vald Hvidt of Denmark, and Arthur Garfield Hays of the United States.

It lasted one week and ended with the conclusion that the defendants were innocent and the true initiators of the fire were to be found amid the leading Nazi Party elite.

Göring was found guilty at the mock trial, which served as a workshop that tested all possible scenarios, and all speeches of the defendants had been prepared.

Another masked witness, whom Hays described as "not very reliable", claimed that Van der Lubbe was a drug addict and a homosexual, who was the lover of Ernst Röhm and a Nazi dupe.