its claimed violation; but as stated, the benchmark for objective reasonableness is that which existed at the time of the alleged violation — we look to the clearly established law at that time.” 114 . See Ba 22 (5th Cir.1997), (upholding against equal protection and due process challenges the "three strikes” provision of the PURA, which bars prisoners form proceeding In Forma Pauperis without advance permission from the court if they have previously filed three or more federal civil lawsuits or appeals that were adjudged frivolous, malicious, or legally insufficient to state a cause of action). 154 . Carson v. Johnson, 112 F.3d at 821-22. 155 . Carson v. Johnson, 112 F.3d at 822. 156 . Carson v. Johnson, 112 F.3d at 822. 157 . See Lewis v. Casey, 518 U.S. at---, 116 S.Ct. at 2179-82, (<HOLDING>); Johnson v. Rodriguez, 110 F.3d 299, 310-11
holding that a prisoners right of access to the courts encompasses only a reasonably adequate opportunity to file nonfrivolous legal claims challenging his conviction or conditions of confinement holding habeas petition challenging denial of custody credits is not related to the conditions of  confinement and was properly brought in the district of conviction recognizing right of prisoners to seek relief under 42 usc  1983 for denial of access to the courts holding that mentally retarded individuals who are involuntarily committed to a state institution have a constitutional right to reasonably safe conditions of confinement under the due process clause of the fourteenth amendment because pjersons who have been involuntarily committed are entitled to more considerate treatment and conditions of confinement than criminals whose conditions of confinement are designed to punish recognizing a liberty interest in reasonably safe conditions of confinement