Story highlights State has rounded up five of seven ex-convicts who "need to be brought back in"

Mistakes made over 13 years are "totally unacceptable and, frankly, maddening," Gov. Jay Inslee says

State has hired two retired prosecutors to look into how the errors began and continued for so long

(CNN) As many as 3,200 convicted offenders were mistakenly released too early from Washington state prisons because of errors in calculating good time credit, officials said Tuesday.

The mistakes occurred over 13 years and began after a state Supreme Court ruling ordered the Department of Corrections to apply "good time" credits earned in county jail to state sentences, Gov. Jay Inslee said.

About 3% of all releases were given excessive "good time" credits. The median number of days that inmates were mistakenly released early is 49 days, officials said.

Correction officials are now trying to locate the ex-offenders who were released too early, and state authorities will ensure the ex-offenders will "fulfill their sentences as required by law," officials said.

Those former inmates, however, will be given "day for day" good credit for their time in the community. Depending on how much time remains to be served on their sentence, offenders will go to work release or back to prison, officials said.

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