In what circumstances will a defendant be able to challenge his conviction and sentence in a separate habeas corpus petition?

The state has a " 'weighty interest in the finality of judgments in criminal cases' " and thus there are rules limiting a defendant's ability to collaterally attack a conviction or sentence. (Gomez v. Superior Court (2012) 54 Cal.4th 293, 309.) For example, procedural rules barring successive habeas corpus petitions " 'are necessary both to deter use of the writ to unjustifiably delay implementation of the law, and to avoid the need to set aside final judgments of conviction when retrial would be difficult or impossible.' " (Id. at p. 308.)