Section 29-21-101 - Grounds for writ(a) Any person imprisoned or restrained of liberty, under any pretense whatsoever, except in cases specified in subsection (b) and in cases specified in § 29-21-102, may prosecute a writ of habeas corpus, to inquire into the cause of such imprisonment and restraint.(b) Persons restrained of their liberty pursuant to a guilty plea and negotiated sentence are not entitled to the benefits of this writ on any claim that: (1) The petitioner received concurrent sentencing where there was a statutory requirement for consecutive sentencing;(2) The petitioner's sentence included a release eligibility percentage where the petitioner was not entitled to any early release; or(3) The petitioner's sentence included a lower release eligibility percentage than the petitioner was entitled to under statutory requirements.Code 1858, § 3720; Shan., § 5500; Code 1932, § 9671; T.C.A. (orig. ed.), §23-1801; Acts 2009 , ch. 420, §§ 1, 2.