Can a defendant challenge his sentence for assault against the Attorney General?

Defendant contends the trial court erred when it restructured his sentence and sentenced him to state prison, rather than to county jail. The Attorney General initially argues defendant is barred from making this challenge because he failed to obtain a certificate of probable cause. However, defendant is not attacking the plea he entered but is challenging the sentence subsequently imposed as not in conformity with the plea agreement. No certificate of probable cause is necessary to make such a challenge. (People v. Brown (2010) 181 Cal.App.4th 356, 360.)

"[W]hen a plea rests in any significant degree on a promise or agreement of the prosecutor, so that it can be said to be a part of the inducement or consideration, such promise must be fulfilled. [Citation.]" (People v. Walker (1991) 54 Cal.3d 1013, 1024, overruled on another ground in People v. Villalobos (2012) 54 Cal.4th 177, 183.) "This does not mean that any deviation from the terms of the agreement is constitutionally impermissible." (Ibid.) "[T]he variance must be 'significant' in the context of the plea bargain as a whole to violate the defendant's rights." (Ibid.)