delivered the opinion of the court:
This case involves a petition for an original writ of mandamus filed in this court. Petitioner, the State, contends that respondent John Teschner, circuit court judge of Du Page County, was precluded from placing respond-*190dent John Slowinski, a defendant in a criminal case and an alleged drug addict, into a drug-rehabilitation program pursuant to the Dangerous Drug Abuse Act (Ill. Rev. Stat. 1977, ch. 911/2, par. 120.1 et seq.), because of the provision in the Unified Code of Corrections (Ill. Rev. Stat. 1977, ch. 38, par. 1005 — 5—3) stating that a defendant may not be sentenced to probation upon his conviction for a Class 2 felony or greater, if he had been convicted of a Class 2 felony or greater within 10 years. We granted leave to file a petition for writ of mandamus. 73 Ill. 2d R. 381(a).
There is little dispute over the facts in the case. Defendant, John C. Slowinski, was charged with the crime of burglary, which had been committed on July 18, 1978. Within the prior 10 years he had twice been convicted of burglary. About November 18, 1974, the defendant was admitted to probation on convictions on two counts of burglary, and on June 9, 1977, defendant was sentenced to two years’ probation for the crime of burglary, conditioned on his receiving treatment through the Gateway House, a drug-rehabilitation program. The defendant was indicted for the July 1978 burglary on September 8, 1978. Before trial, the defendant petitioned the court to elect to be treated as a narcotic addict under the Dangerous Drug Abuse Act and to be placed under the supervision of the Department of Mental Health for treatment. Judge Teschner ordered the Department of Mental Health to conduct an examination of the defendant to determine whether he was an addict and the likelihood of his being rehabilitated through treatment. Judge Teschner found defendant guilty of burglary and sentenced him to 36 months’ probation conditioned upon successful completion of the Gateway Program.
Because the defendant was convicted of three Class 2 felonies in less than 10 years, under the express terms of the Unified Code of Corrections (Ill. Rev. Stat. 1977, *191ch. 38, par. 1005 — 5—3) he was not eligible for a sentence of probation. Throughout the briefs the State treats the action of Judge Teschner as being a sentence under the Unified Code of Corrections and speaks of the judge having “sentenced” the defendant to probation. However, in the present case, the defendant elected to be treated under the Dangerous Drug Abuse Act instead of being prosecuted under the Code of Criminal Procedure of 1963 (Ill. Rev. Stat. 1977, ch. 38, par. 100 — 1 et seq.). Under the Act, “probation” is not a sentence but is a method devised by the legislature for treating those who qualify for treatment. Under the Act, the word “probation” carries a different connotation than it does under the Unified Code of Corrections.
Under the Dangerous Drug Abuse Act, an addict charged with or convicted of a crime may elect to apply for treatment if he meets the eligibility standards set out in section 8 (Ill. Rev. Stat. 1977, ch. 9114, par. 120.8). In relevant part, this section states that “[a]n addict charged with or convicted of a crime is eligible to elect treatment under the supervision of the Department [of Mental Health] instead of prosecution or probation, as the case may be ***.” (Emphasis added.) (Ill. Rev. Stat. 1977, ch. 9114, par. 120.8.) From the express wording of the statute, it is apparent that the legislature intended treatment under the Dangerous Drug Abuse Act to be an alternative to the normal ambit of prosecution or sentencing under the Unified Code of Corrections. Thus, if a person is charged with a crime but not convicted, he may elect treatment under the Act instead of prosecution under the Code of Criminal Procedure of 1963 (Ill. Rev. Stat. 1977, ch. 38, par. 100 — 1 et seq.). If he has been convicted, he may elect treatment under the Act in lieu of a sentence to probation under the Unified Code of Corrections. Section 9 of the Act sets forth the procedure if the person has been charged with a *192crime but not convicted. (Ill. Rev. Stat. 1977, ch. 9114, par. 120.9.) Section 10 of the Act sets forth the procedure if the person who elects treatment has been convicted. Ill. Rev. Stat. 1977, ch. 911/2, par. 120.10.
This court, on several occasions, has reviewed the Dangerous Drug Abuse Act and noted the differences between it and the Unified Code of Corrections. As this court stated in People v. Phillips (1977), 66 Ill. 2d 412, 416, “The Act provides an alternative to the usual criminal justice procedures; it allows a criminal defendant with a drug abuse problem to avoid the criminal justice machinery ***.” The treatment under the Act, unlike a sentence, is not a consequence of defendant’s guilt. It is instead an alternative to a criminal conviction and the regular sentencing alternatives available under the Unified Code of Corrections. [People v. Warren (1977), 69 Ill. 2d 620; People v. Phillips (1977), 66 Ill. 2d 4:12; People v. McCoy (1976), 63 Ill. 2d 40.) Also, section 2 of the Act indicates a strong legislative policy favoring the prevention of drug abuse and encouragement for the treatment and rehabilitation of drug addicts. (Ill. Rev. Stat. 1977, ch. 9114, par. 120.2.) It is apparent that the legislature felt that the treatment for drug abuse requires more medical and social treatment than can be provided under the present criminal justice system through a sentence of probation with conditions imposed Concerning treatment of the drug problem.
Probation, as used in the Dangerous Drug Abuse Act, is merely descriptive of the status of the individual when and if he is accepted for treatment and is not used in the same context under the Unified Code of Corrections. Under the former provisions of the Code of Criminal Procedure of 1963 (Ill. Rev. Stat. 1971, ch. 38, par. 117 — 1), probation was not a sentence but rather a suspension of sentence. (See People v. Ward (1975), 32 Ill. App. 3d 781; People v. Gentry (1972), 5 Ill. App. 3d 1088.) *193However, under the Unified Code of Corrections (Ill. Rev. Stat. 1977, ch. 38, par. 1005 — 5—3(d)) it is specifically referred to as a sentence. (See People v. Brown (1975), 32 Ill. App. 3d 10;People v. Meyer (1975), 30 Ill. App. 3d 673.) Under the Dangerous Drug Abuse Act, probation is not considered a sentence. Under the language of the Act, one is not “sentenced” to probation as under the Unified Code of Corrections but rather “placed” on probation. (Ill. Rev. Stat. 1977, ch. 911/2, par. 120.10.) This is similar to the term “admitted to probation” used in the Code of Criminal Procedure of 1963 (Ill. Rev. Stat. 1971, ch. 38, par. 117 — 1 et seq.), prior to the effective date of the Unified Code of Corrections. In reviewing the record we note that the trial court used form orders, designed for use under the Unified Code of Corrections, that indicate the defendant was sentenced to probation. However, due to the trial judge’s clear intent to deal with the defendant under the Dangerous Drug Abuse Act, we will not permit the substance of the judge’s orders to be controlled by the form.
We have held on previous occasions that the term “probation” may have different meanings in different statutes. In People v. DuMontelle (1978), 71 Ill. 2d 157, interpreting the Cannabis Control Act (Ill. Rev. Stat. 1973, ch. 561/2, par. 710), we held that probation under that act did not amount to a sentence. In our case the trial court’s exercise of discretion in admitting a defendant to probation and requiring treatment under the Dangerous Drug Abuse Act is a disposition imposed as a rehabilitative treatment rather than a criminal sanction. Thus, we hold that the provisions of the Unified Code of Corrections are not controlling in this case and should not be superimposed upon the provisions of the Dangerous Drug Abuse Act to prohibit a disposition of probation authorized under that act.
During oral argument the State argued in the alter*194native that Judge Teschner did not comply with the provisions of the Dangerous Drug Abuse Act. As this court has previously stated, the burden rests on the petitioner to show that he has a clear legal right to the writ. (People ex ex rel. Latimer v. Board of Education (1946), 394 Ill. 228.) The petitioner for mandamus must set forth every material fact necessary to show that he is entitled to the writ. [Daniels v. Cavner (1949), 404 Ill. 372; People ex rel. Callahan v. Whealan (1934), 356 Ill. 328; People ex rel. City of Chicago v. Board of Review (1927), 326 Ill. 124.) After carefully reviewing the Act and the facts in the record, there is no indication that the trial court did not comply with the Act.
Lastly, we are cognizant of the recently enacted Public Act 81 — 851 (approved and effective September 20, 1979) that amended section 10 of the Dangerous Drug Abuse Act to specify that a court may place a person on probation for treatment, as provided under the Act, “if such a sentence is consistent with Section 5 — 6—1(a) of the Unified Code of Corrections ***” (Ill. Rev. Stat. 1979, ch. 911/2, par. 120.10). The effective date of September 20, 1979, of this amendment is subsequent to the date of sentencing of the defendant and is not applicable to this case.
For the reasons stated, we decline to issue the writ of mandamus directing Judge Teschner to vacate his dispositional order.
Writ denied.