The Registration Acts - the Mutant Registration Act (or MRA) and Super-human Registration Act (SRA or sometimes SHRA) - are controversial legislative bills which, when passed into law, enforce the mandatory registration of super-powered individuals with the government.
As their names suggest the Mutant Registration Act and the Superhuman Registration Act deal with the registration of mutants and of super-humans respectively. Numerous versions of each bill have been proposed at different times and in different jurisdictions.
Days of Future Past
Kate Pryde psychically travels back in time from a dystopian future to the present and possesses the body of her younger self, X-Men member Kitty Pryde. On revealing herself to Kitty's team-mates she recounts to them the series of events which led to her dark future, in the hopes that the X-Men might be able to prevent those events from coming to pass.
One of those pivotal events was the passing of a "Mutant Control Act" by the government of the United States. When the Supreme Court found the law unconstitutional the government responded by reactivating their robot Sentinel program so that they might police the mutant race. The Sentinels interpreted their mandate in such a way that they decided to forcibly take over the government of the country and instituted a harsh regime where mutants were severely persecuted.
The reference to the Mutant Control Act is brief and it is unclear exactly what its provisions would entail, though it would appear that registration forms at least one part of it.
The X-Men are successful in preventing one of the pivotal events which Pryde had described to them (the assassination of Senator Robert Kelly) from occurring, though the it is ambiguous as to whether Pryde's dystopian future was fully avoided.
Robert Kelly decided the registration of mutants by the government is a necessity. Kelly discussed his introduction of the bill with a senatorial colleague. The Act was mentioned, passed as legislation, and accepted as law, suggesting that, unlike the Mutant Control Act in the "Days of Future Past" timeline, it would not be repealed by the Supreme Court.
Government agent Val Cooper and the mutant terrorist Mystique formed Freedom Force a government sanctioned superhero team (mostly comprising former members of the Brotherhood of Evil Mutants). Freedom Force sought to enforce the MRA by arresting unregistered mutants such as members of the X-Men, X-Factor and the New Mutants.
Captain America V (John Walker, later known as U.S. Agent) and Battlestar, who were, like Freedom Force, officially sanctioned, also briefly enforced the Act by capturing the unregistered mutant Meteorite for the government.
During this period of active enforcement of the MRA, the only mutants who publicly protested the Act were those who were not aligned with the X-Men or its affiliated teams. For example, the Alliance of Evil demonstrates against the MRA in Manhattan and after fighting X-Factor are arrested by Freedom Force and a mutant group called the Resistants protested the Act in Washington D.C.. Indeed far from publicly agitating against the act, X-Factor, actually pretended in public to be supporters of the MRA who were actively enforcing it, though in actuality they acted to subvert it.
After Xorn attacked Manhattan posing as Magneto and causing riots and casualties across the city, the mutants were allegedly threatened in virtually every country by projects to make them outlaws, to brand them, to deprive them from their rights to breed or to incarcerate them into concentration camps.
A variation on the concept of the Mutant Registration Act, the Super-human Registration Act was proposed. During that period, the Fantastic Four went to Congress where a committee was investigating whether a SRA, similar in its provisions to the already in effect Mutant Registration Act, was required for Super-heroes (the MRA only covered individuals who had their powers inherently at birth, not those who acquired their abilities artificially in later life).
In his testimony and in evidence he presented to Congress, Reed Richards argued that a Super-human registration Act was unnecessary as Super-humans had been largely effective and trustworthy in their actions and government regulation would only stifle their ability to protect the world. He argued that those individuals who were likely to act irresponsibly with their powers were also likely to be super-villains and thus would not be candidates for registration anyway.
As the topic was debated he and his teammates were continually attacked by random super-villains whom they easily subdued, though it was unclear if this helped or hinders his arguments. In his final point concerning the lack of any workable definition of super-human Richards demonstrated a device that could scan a human for physical and mental capabilities and compared those to the national average, marking 'significant outliers' as "super-human". The device identified several regular humans, including some committee members, as "super-human" according to those criteria. The proposed legislation was abandoned and registration of super-humans in the United States was not recommended by the committee.
Canadian Super-Powers Registration Act
However the Super-Powers Registration Act was later passed by the Canadian government. Introduced by a minister of the Canadian government called Robert Hagon, the Super-powers Registration Act was part of a complex plot engineered by the Master using the alias "Joshua Lord".
The terms of the act entail the government employment of all super-powered individuals, including mutants, who were then enlisted in one of the government Department H "Flight" programs such as "Alpha Flight" and "Gamma Flight". The Act was controversial and led to the disbandment of the Canadian government's super-teams (the various "Flights").
Following "M-Day" and the sudden dramatic fall in the Mutant population, the U.S. government again considered a Superhuman Registration Act and Spider-Man and Iron Man traveled to Washington, D.C. to discuss the issue. Iron Man was initially opposed to the idea, while Spider-Man was unsure of his opinion.
Iron Man attempted to persuade his Illuminati colleagues to support the SRA in order to diffuse it. Iron Man predicted that some super-human or group of super-humans would eventually make a mistake that would cost hundreds of lives (he specifically mentioned the Young Avengers and the Runaways as candidates for causing such a catastrophe). After such an event, he went on to predict, the government would inevitably rush to make an example of someone, or everyone, in the super-human community by passing legislation that would be even more restrictive or draconian towards them then the proposed SRA. By supporting the Act before it was passed, he suggested, he and his fellow Illuminati might have been able to help avert such possible future tragedies and also, by becoming a part of the process, help moderate the legislation so that it would have the minimum possible negative effect on the super-human community.
The first part of Iron Man's prediction was proven to be accurate when a conflict between the New Warriors and a group of super-villains ended with a massive explosion which killed hundreds of children attending a nearby school. The public outcry that followed this event led the government (with the support of Iron Man and other Illuminati such as Reed Richards) to quickly enact the SRA.
This led to a major schism and conflict among the super-heroes, with one side (led by Captain America) opposed to the SRA resisting registration and the other side (led by Iron Man) supporting registration and trying to enforce the new law.
Terms of the Registration Acts
The Act requirement that super-powered individuals surrender their real names to the government (but not the public). This obviously entails the loss of their secret identities.
It enables the government to monitor all powered individuals and is drafted to facilitate the government's licensing and/or employment of individuals who are actively using their powers. The powered individual must fulfill some requirements or meet some criteria before they are allowed to fully use their abilities and gain legal authorization to continue to use their abilities to fight crime. Government employment is not mandatory, though it is available to those who wish to take it.
Alternate universe Registration Acts
In Exiles #12 a parallel world is shown, similar to the "Days of Future Past" timeline, in which the passing of a Mutant Registration Act led to the Sentinels taking over the world and herding mutants, Super-humans and eventually even humans into concentration camps.
The "Age of Apocalypse" version of Sabretooth, who at that point was a member of the Exiles, stayed on this planet in order to raise the infant David Richards (the son of the Rachel Summers and Franklin Richards of that reality).
Marvel Knights: 2099
After the passage of this act the Avengers, X-Men and Fantastic Four opposed the government's enforcement of it and were eventually defeated in a major battle that was fought in front of the Baxter Building. This led all the remaining super-heroes to go underground.
Jubilee's parents were worried that they may have to "register her with The Mutant Control Agency" after she manifests her powers for the first time. After the attack on Jubilee at a mall, the X-men uncovered that the group running the registration act were using it as a front to secretly eliminate mutants by tricking them into identifying themselves. This was all part of Henry Gyrich's plot to which he believes that mutants are an immediate danger to society and must be eliminated by the Sentinels which his associate Bolivar Trask had created.
After the X-Men raided the Mutant Control Agency to destroy their files, when meeting with Gyrich, the president decided to cancel the Registration Act. The government's persecution of Mutants is a consistent theme throughout the 5th season of the series.
It is the prospect of this proposed legislation that motivates Magneto in his schemes in the film, as he sees it as persecution towards mutants. He is eventually successful in replacing Kelly with Mystique who impersonates the Senator and removes the Act from consideration.
The Emergency Powers Act.
The Registration Acts as a concept
The idea that super-powered individuals might need to be "registered" by the government was first raised in specific relation to mutants. Moira MacTaggert) brings up the notion of "registration" in reference to a politician whom she suspects of anti-mutant bigotry she says:
- "Registration today, gas chambers tomorrow".
The same issue features mention of the "Mutant Control Act", however it is left unclear exactly what that legislation involves and whether some form of registration is a part of it.
The term "Mutant Registration Act" was first fully used in Uncanny X-Men #181, by writer Chris Claremont. As the MRA (as it became known) was passed into law in the Marvel Universe it became widely used as a subplot, plot device or background element across Marvel's entire line of titles, especially those featuring mutants (such as Uncanny X-Men, X-Factor and New Mutants) during the late-1980's.
In the early 1990's Chris Claremont left the X-titles and the topic of the MRA began to appear much more rarely in stories. It was still occasionally mentioned, though usually in the past tense, suggesting that it was repealed at some point (though this was never clearly shown) or that it simply ceased to be actively enforced.
However, in an interview regarding the Civil War: X-Men limited series its writer David Hine suggested that it is still law in the Marvel Universe, stating that in the series the idea of bringing "the Mutant Registration Act in line with the SRA" will be discussed. 
The idea of an equivalent piece of legislation for non-mutant super-powered individuals - a Super-human Registration Act - was first raised in comics that were published during the "Acts of Vengeance" crossover in 1990. The issue was most fully explored in Fantastic Four #335 and #336 by writer Walter Simonson. In the course of the story the issue was apparently resolved with the proposed Act being shelved.
The concept was then revived in 1993 in Alpha Flight #120 (1993) by writer Simon Furman. In that issue a "Super-powers Registration Act" becomes law in Canada and went on to be a major plot point in the remainder of the series. However later Alpha Flight series did not make use of the concept.
In 2006 the concept was again revived by writer Mark Millar as the main plot point in Marvel's 2006 Civil War crossover. In preparation for that storyline a new version of the Super-human Registration Act has been widely mentioned across various Marvel titles, with the issue being most widely discussed and explored in Amazing Spider-Man #529 and #531 (April - June, 2006) by writer J. Michael Straczynski.
Issues, allegories and metaphors
The issue has generally been portrayed in broad terms as being a debate between the rights of the individual (to freedom of action and expression etc.) on one side versus the rights of society at large (to safety from danger or harm) on the other. Does the super-powered individual (mutant or otherwise) have an absolute right to their abilities or does society have a right to constrain or at least monitor them and their expression of those abilities?
Debate on the topic of the registration of super-heroes or mutants as presented in Marvel Comics has generally tended to be slanted in favor of the anti-registration argument, due to the fact that the protagonists of the comics are the powered individuals - the people whose freedoms might be compromised by any such law.
As such the issue has most often been explored in a civil rights context, with the various Acts portrayed as acts of persecution seeking to legislate against a minority group whose minority status is basically innate - an obvious parallel with the struggle of many minority groups against prejudice.
This was especially been the case in the X-Men stories of Chris Claremont, in which the "Act" pertains to mutants (the MRA). The plight of mutants has traditionally been used as an allegory for the struggles of real world minorities such as African Americans and in Claremont's (and other contemporary comic writers in the 1980's) stories the passing of the Mutant Registration Act is generally treated as a negative development, a harbinger of a more repressive climate for mutants, foreshadowing the possible post-apocalyptic future first shown in the "Days of Future Past" storyline.
When the topic of the original Super-human Registration Act is debated in Fantastic Four #335 and #336 the issue is explored in a national security context, with the utility of such a law being challenged. In the comics the Fantastic Four argue that super-heroes are already a hugely benevolent force for society and such an act would be unnecessary and possibly counter-productive.
When the issue of an SRA was raised again in Amazing Spider-Man #529#531 the prospect of a new SRA is explored once more from a security perspective, with reference being made to the fact that individual super-powered individuals often wield abilities which have massively destructive potential for use, making some mechanism to regulate their activities necessary. As such comparisons and allusions are made to real world issues such as gun control and arms control.
Civil War explored the "civil rights" implications of the SHR as previous stories had done, but also explored the other side of the argument in more depth, in particular how super-heroes were absent a SRA, illegal vigilantes, lacking proper legal authority or oversight.
- The concept has been most extensively explored in comic books, though a version of them has featured in both the original X-Men animated series and the X-Men films. The first mention of the broad concept was in X-Men #141 (January, 1981). The term "Registration Act" was first used in Uncanny X-Men #181 (May, 1984). A newly-passed into law Super-human Registration Act is a major plot point in the 2006 limited series Civil War.