Fake Death Note Rules

For the genuine rules see Rules of the Death Note

The Fake Death Note Rules are two rules which Light Yagami persuades the Shinigami Ryuk to write into the Death Note as part of a plan to clear him of suspicion but which ultimately lead to his downfall.

Fake Rules

 * 1) If the user of the Death Note does not write a name in the Note for 13 days, he or she will die.
 * 2) If the Death Note is torn up or destroyed, all the humans who have touched it will die.

Plot
When Misa Amane was taken into custody on the suspicion of being the Second Kira, the Shinigami Rem told Light that he had to free her or else Rem would kill him. Light himself knew that it was only a matter of time before L would arrest him as the original Kira and therefore came up with a plan which would clear both his name and Misa's.

As part of the process, Light got Ryuk to write two extra false rules in the Death Note alongside the genuine ones. He then entrusted this Death Note to Rem and got her to pass it on to another unknown human.

Light then surrendered to L and the rest of the Kira Task Force and was incarcerated. He and Misa were kept isolated in single cells with their hands bound. Meanwhile, Rem let another human take possession of her Death Note which he used to resume the Kira killing of criminals as well as furthering his own ends.

Light and Misa renounced their ownership of their respective Death Notes, a side effect of which caused them to lose all memory of ever using them and therefore of being either Kira or the Second Kira. They now genuinely believed themselves to be innocent of any crimes and their jailers were persuaded to release them. They then joined forces with L in order to track down the new Kira (as per Light's plan). This turned out to be Kyosuke Higuchi who was arrested and his Death Note seized by L, Light and the police. Once he touched it, Light recovered all his memories of being Kira and set into motion the next stage of his plan: the killing of his nemesis, L.

The "13 day" rule went further in establishing Light and Misa's innocence in the eyes of the Kira Task Force since they had been held in custody for over 50 days with no possible access to the Death Note; while the other rule made the police reluctant to destroy the Death Note since many of them had touched it as well.

Misa later regained her own memories of being the Second Kira by recovering a second Death Note which Light had hidden. She then used it in order to resume the killing of criminals. When crooks again started to die of heart attacks, L noted how this was so soon after Misa's surveillance had been lifted.

L was not convinced that the "13 day" rule was genuine since there was still plenty of other evidence that pointed to Misa being the Second Kira. He thus contacted his associate Watari, charging him with finding two Death Row inmates who could test the Death Note: one would write down the name of the other, who would die, and they would be able to see if the writer would die after thirteen days or not.

Rem realised that this would expose the rule as a fake, that Misa would again be the focus of the investigation and that it would destroy what life and happiness she had left &mdash; having twice made the deal for the Shinigami Eyes and halved her life expectancy on both occasions. Rem therefore used another Death Note in order to kill L and Watari but this also caused her own death since she had killed in order to purposely extend Misa's life span.

The rest of the Kira Task Force had opposed L's method of testing the Death Note and, following his death, kept it under lock and key without trying it out or destroying it.

In the long term, however, the "13 day" rule proved to be a factor in Light's undoing, since L's successors Mello and Near discovered for themselves that it was a fake and passed this on to the Kira Task Force, planting the seeds of doubt about Light, who was now leading the group. Aizawa and Mogi in particular began to again suspect that Misa and Light were the original Kiras (even though they wanted to believe that Light isn't Kira due to thinking of his father Soichiro Yagami) and kept them under watch while also supplying Near with vital information. When Light was finally exposed as Kira and killed, Ryuk confirmed that the two rules were false and Near was thus able to destroy the Death Notes.