F I L E D
                                                                          United States Court of Appeals
                                                                                  Tenth Circuit
                          UNITED STATES COURT OF APPEALS
                                                                                   JAN 28 1997
                                      TENTH CIRCUIT
                                                                             PATRICK FISHER
                                                                                       Clerk
 REUBEN LEE THOMAS,

           Petitioner-Appellant,

               v.                                              No. 96-5192
                                                          (D.C. No. 96-C-204-K)
 DENISE SPEARS, Warden; ATTORNEY                               (N.D. Okla.)
 GENERAL OF THE STATE OF
 OKLAHOMA,

           Respondents-Appellees.




                                   ORDER AND JUDGMENT*


Before ANDERSON, HENRY, and BRISCOE, Circuit Judges.


       After examining the briefs and appellate record, this panel has determined

unanimously that oral argument would not materially assist the determination of this

appeal. See Fed. R. App. P. 34(a); 10th Cir. R. 34.1.9. Therefore, the case is ordered

submitted without oral argument.

       Petitioner Reuben Thomas has filed an application for a certificate of appealability

to appeal the district court's denial of his 28 U.S.C. § 2254 petition for writ of habeas

corpus. 28 U.S.C. § 2253(c)(1)(A); Fed. R. App. P. 22(b). Petitioner is presently



       *
          This order and judgment is not binding precedent, except under the doctrines of
law of the case, res judicata, and collateral estoppel. The court generally disfavors the
citation of orders and judgments; nevertheless, an order and judgment may be cited under
the terms and conditions of 10th Cir. R. 36.3.
incarcerated in Oklahoma following his 1986 conviction in state court. We conclude

petitioner has not made "a substantial showing of the denial of a constitutional right"

under § 2253(c)(1)(A) and deny the certificate of appealability.

       Petitioner challenges calculation of his good-time credits, arguing the method of

computation of such credits violates the ex post facto clause. He contends that during the

period of April 1989 until October 1991 he was wrongly classified under the 1988 version

of 57 O.S. § 138 in a credit class level that prevented earning good-time credits through

work. He also argues that work he did from October 1991 to May 1993 resulted in good-

time credits computed under the law then in effect rather than the law in effect at the time

the crime was committed, which would have allowed him three days' credit for each day

worked.

       At the time petitioner committed the crime for which he is incarcerated, good-time

credits could be earned through work, school attendance, or participation in a vocational

training program. See 57 O.S.A. § 138, Historical and Statutory Notes. Service or

maintenance work for another state agency, county, or municipality performed by an

inmate under 57 O.S. § 224 earned an inmate three days' credit for each earned day of

service. See 57 O.S.A. § 224, Historical and Statutory Notes. In 1988, the statutes

governing good-time credits changed and credit was no longer based on work but on the

class to which a prisoner was assigned by an adjustment review committee. 57 O.S. §

138(B). Inmates classified in class one earned no credits; inmates in the other classes

earned 22 to 44 credits per month. 57 O.S. § 138(C)(2). Petitioner was placed in class

one in March 1989 and earned no credits from April 1989 until he advanced to class two

in January 1991.


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       Petitioner was convicted before the four-class system was enacted and he is

entitled to allowable credits under the law in effect on the date the crime giving rise to his

conviction was committed. State ex rel. Maynard v. Page, 

(Okla. Cr. App.

1990). Consequently, he can claim no liberty interest in any aspect of the four-class

system. His contention that other inmates' advancements to higher classes violated equal

protection principles is unconvincing. Petitioner does not allege discretionary decisions

regarding classifications are based on any suspect class. Therefore, to pass constitutional

muster, the challenged actions need only be reasonably related to some legitimate

penological purpose. Templeman v. Gunter, 

, 371 (10th Cir. 1994). By

statute, classification decisions are based on a number of factors, including

"rehabilitation, obtaining job skills and other educational enhancement, participation in

and completion of alcohol/chemical abuse programs, incentives for inmates to accept

work assignments and jobs, work attendance and productivity, conduct record,

participation in programs, cooperative general behavior, and appearance." 57 O.S. §

138(B). In light of the deference this court must afford prison officials in executing their

discretionary judgments, see Hewitt v. Helms, 

, 472 (1983), petitioner's

equal protection claim cannot stand.

       Petitioner appears to contend that applying the class system rendered him

ineligible to work, depriving him of a liberty interest in the opportunity to earn good-time

credits. The law in effect at the time petitioner committed the offense for which he is

incarcerated did not guarantee an inmate the opportunity to work and earn good-time

credits. Gardner v. Benton, 

(1977). Thus, reclassifications that impact

eligibility for work do not deprive inmates of due process. 

alleges the credit he was given for work from January 1991 to March

1993 was based on his class assignment rather than on the statutes in effect at the time he

committed the offense. He presents nothing to establish his good-time credits were not

computed in a manner at least as beneficial to him as the statutes then in effect. The

record is devoid of any showing that petitioner performed sufficient work during any

period in which he was assigned credit based on his class where he would have been

entitled to more credit under the prior system. The Oklahoma Department of Corrections

"now tabulates for each inmate how many credits he has earned under each version of the

statute [37 O.S. § 138] on a monthly basis and automatically awards the inmate the

greater of the two totals." Turnham v. Carr, 

(10th Cir. 1994) (table). As

petitioner has made no showing that his credits were calculated in a way prejudicial to his

expectations, he has presented no substantial showing of any ex post facto violation. See

Devine v. New Mexico Dept. of Corrections, 

, 341 (10th Cir. 1989) (ex post

facto law must disadvantage affected offender).

       The application for a certificate of appealability is DENIED and this appeal is

DISMISSED. The mandate shall issue forthwith.

                                                  Entered for the Court

                                                  Mary Beck Briscoe
                                                  Circuit Judge




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