In 2006 Ceasar Cantu of Katy, Texas, pleaded guilty to in a Virginia court of charges related to drug trafficking and money laundering.
Stipulations in Cantu's plea agreement called for a sentencing guideline for a base offense level of 34. But a typographical error in his pre-sentence report mistakenly assigned him a base offense level of 36, which increased his sentence by 42 months.
A judge ruled that Cantu did not discover the error in time to correct it through judicial means, so the situation now only can be rectified through presidential clemency, according to an explanation from a White House official.
The original sentence carried a punishment of 180 months imprisonment and five years supervised release. Obama commuted the sentence to 138 months imprisonment.