delivered the opinion of the court:
Petitioner, Joseph Perruquet, appeals from a judgment of the circuit court of Williamson County which dismissed, as frivolous, his petition for post-conviction relief. On this appeal, petitioner argues that he should not have received an extended-term sentence of 30 years’ imprisonment on his conviction for aggravated kidnapping because that was not the most serious offense for which he was found guilty. We agree. For the reasons which follow, we therefore reverse the judgment dismissing the petition and modify petitioner’s sentence on the aggravated kidnapping conviction.
The circumstances giving rise to this appeal are not in dispute. Following a jury trial in the circuit court of Williamson County, petitioner was convicted of deviate sexual assault, two counts of rape, and aggravated kidnapping. The circuit court sentenced him to extended terms of 60 years on each of the convictions for deviate sexual assault and rape, which were Class X felonies (see Ill. Rev. Stat. 1981, ch. 38, pars. 11—1(c), 11—3(b)). Thé court also gave defendant an extended-term sentence, this one for 30 years, on the conviction for aggravated kidnapping, a Class 1 felony (see Ill. Rev. Stat. 1981, ch. 38, par. 10— 2(bX2)). Two of the 60-year sentences were to be served consecutively, while the remaining sentences were to be served concurrently.
On direct appeal to this court, the circuit court’s judgment was affirmed. (People v. Perruquet (1983),
We expressly rejected this argument. (See Perruquet,
Petitioner subsequently filed a petition for post-conviction relief. As we have indicated, that petition was dismissed as frivolous, and petitioner has appealed. On this appeal, petitioner argues simply that in light of People v. Jordan (1984),
Although the supreme court’s decision in People v. Jordan (1984),
The State nevertheless argues that the question of whether petitioner should have received an extended term for aggravated kidnapping is simply a matter of statutory construction and that erroneous statutory construction is not an issue of constitutional magnitude which is cognizable in a post-conviction proceeding. We note, however, that under Jordan, the extended-term sentence imposed by the circuit court on the aggravated kidnapping conviction exceeded what was authorized by statute. Where a court imposes a sentence in excess of what a statute permits, the legal and authorized portion of the sentence is not void, but the excess portion of the sentence is void. (In re C.T. (1985),
The State further argues that petitioner should not be allowed to challenge the extended-term sentence because: (1) the issue was previously decided against him by this court on direct appeal and is therefore res judicata; and (2) the question of whether the extended-term sentence was proper was not raised by petitioner at the circuit court level in this case and has therefore been waived. Neither of these claims has merit.
Principles of res judicata will not bar relitigation of a claim in a post-conviction proceeding where fundamental fairness so requires. (People v. Smith (1985),
We likewise believe that petitioner’s failure to challenge the propriety of his extended-term sentence at the circuit court level in this proceeding should not bar our consideration of the issue on grounds of waiver. This is so for two reasons. First, the improper sentencing of petitioner to an extended-term on the aggravated kidnapping conviction is cognizable by this court under the doctrine of “plain error.” (People v. Bivens (1987),
For the foregoing reasons, the judgment of the circuit court of Williamson County dismissing petitioner’s post-conviction petition is reversed, and petitioner’s sentence for his conviction for aggravated kidnapping is modified to 15 years’ imprisonment, the maximum sentence of imprisonment authorized by statute for a Class 1 felony. (See Ill. Rev. Stat. 1981, ch. 38, par. 1005 — 8—1 (a)(4).) We order this modification pursuant to our authority under Supreme Court Rule 615(b) (107 Ill. 2d R. 615(b)).
Reversed; sentence modified.
