This rule now gathers all the sanctions specified in the appellate rules into one rule and broadens the powers of the court by the addition of (e).
 Prior subsections (b), entitled, "Consequence of Failure to File Brief," (c), entitled, "Failure to Prosecute Appeal," and (e), entitled "General Powers of the Court," have been deleted. The relevant substance of these prior subsections has been combined and condensed and now appears in revised subsection (a).
 The statement contained in prior subsection (b) that the court may dispense with oral argument if an appellant or cross-appellee fails to file a brief has been deleted from the Rule because, pursuant to C.A.R., whether to allow oral argument is always at the discretion of the appellate court.
 Because prior subsections (b), (c), and (e) were deleted, prior subsection (d), entitled "Sanctions for Frivolous Appeal," has been re-lettered to subsection (b).
Annotation Law reviews. For comment, "Attorney Fee Assessments for Frivolous Litigation in Colorado", see 56 U. Colo. L. Rev. 663 (1985). Due process considerations. When an appellate court imposes sanctions upon an appellant, due process requires that the appellant be afforded certain protections before being deprived of his property. He is entitled to notice and an opportunity to respond. Mission Denver Co. v. Pierson, 674 P.2d 363 (Colo. 1984). Award against state for damages may only be ordered if authorized by statute. People in Interest of A.L.B., 683 P.2d 813 (Colo. App. 1984). No basis for damages where genuine issue in dispute. There is no basis for an award of damages pursuant to this rule where there is a genuine disputed issue in the matter on appeal. Rocky Mt. Sales & Serv., Inc. v. Havana RV, Inc., 635 P.2d 935 (Colo. App. 1981). Even where trial court's entry of summary judgment in favor of defendant is upheld on appeal and no genuine issue of material fact is found to have existed, plaintiff's appeal is not automatically frivolous and defendant's request for fees may be denied. Price v. Conoco, Inc., 748 P.2d 349 (Colo. App. 1987). Appeal held not frivolous because of absence of Colorado authority on the question forming basis of appeal. Jorgenson Realty, Inc. v. Box, 701 P.2d 1256 (Colo. App. 1985). Abuse of discretion. In light of the significance of the issues on appeal (i.e., the state's obligation to maintain state prisoners in state correctional facilities and to reimburse counties for confining state prisoners) and the fact that both petitioner and respondent sought appellate review, court of appeals abused its discretion in dismissing case for failure to timely transmit the record. Dept. of Corr. v. Pena, 788 P.2d 143 (Colo. 1990). Substantiality of issues. When determining whether dismissal is an appropriate sanction for failure to timely transmit the record, an appellate court should consider the substantiality of the issues on appeal and the full range of possible sanctions and should select the sanction most appropriate under the circumstances. Dept. of Corr. v. Pena, 788 P.2d 143 (Colo. 1990). Because the theory propounded on appeal was not a "relitigation" of a settled issue, wholly lacking in precedential support, devoid of a plausible rationale, or brought vexatiously, it cannot be said to be "frivolous". Wood Brothers Homes, Inc. v. Howard, 862 P.2d 925 (Colo. 1993) (decided under former Â§ 13-80-127 ); Adams v. Land Servs., Inc., 194 P.3d 429 (Colo. App. 2008). Damages not awarded where amount not specified. Where a number of the issues raised by the appellant are frivolous, but where the appellee has not specified an amount requested for damages, the appellate court will decline to award damages. In re Mann, 655 P.2d 814 (Colo. 1982). Appeal should be considered frivolous if the proponent can present no rational argument based on the evidence or law in support of a proponent's claim or defense, or the appeal is prosecuted for the sole purpose of harassment or delay. Mission Denver Co. v. Pierson, 674 P.2d 363 (Colo. 1984). Appeal held to be frivolous, and attorney's fees assessed. Rogers v. Charnes, 656 P.2d 1322 (Colo. App. 1982); Artes-Roy v. City of Aspen, 856 P.2d 823 (Colo. 1993); In re Purcell, 879 P.2d 468 (Colo. App. 1994); Martin v. Essrig, __ P.3d __ (Colo. App. 2011). An appeal "lacks substantial justification" and is "substantially frivolous" when the appellant's brief fails to set forth, in a manner consistent with C.A.R. 28, a coherent assertion of error supported by legal authority. As a result, it is appropriate to assess attorney fees against the attorney prosecuting the appeal in this case. Castillo v. Koppes-Conway, 148 P.3d 289 (Colo. App. 2006). Because appeal is not frivolous, court denies defendants' request for their appellate attorney fees pursuant to paragraph (d) of this rule. Lobato v. Taylor, 13 P.3d 821 (Colo. App. 2000), rev'd on other grounds, 71 P.3d 938 (Colo. 2002). Board of education is entitled to reasonable attorney fees incurred in defending claim of breach of duty to teach morality in public schools where plaintiff relied primarily on overruled case law, constitutional and statutory provisions that imposed no duty, and where plaintiff presented no rational argument based on existing law. Skipworth v. Bd. of Educ., 874 P.2d 487 (Colo. App. 1994). A claim is frivolous if the proponent can present no rational argument based on the evidence or the law in support thereof. Such test encompasses appeals that are manifestly insufficient or futile. Lego v. Schmidt, 805 P.2d 1119 (Colo. App. 1990). No sanctions awarded for frivolous appeal even though the court rejected appellants' public policy argument. In re Estate of Schlagel, 89 P.3d 419 (Colo. App. 2003). Request for costs pursuant to this rule denied. Dewar v. LeNard, 653 P.2d 82 (Colo. App. 1982); People ex rel. A.R.D., 43 P.3d 632 (Colo. App. 2001). Applied in In re Estate of Perini, 34 Colo. App. 201, 526 P.2d 313 (1974); In re Trask, 40 Colo. App. 556, 580 P.2d 825 (1978); Sports Premiums, Inc. v. Kaemmer, 42 Colo. App. 172, 595 P.2d 696 (1979); Applewood Gardens Homeowners' Ass'n v. Richter, 42 Colo. App. 510, 596 P.2d 1226 (1979); In re Erickson, 43 Colo. App. 319, 602 P.2d 909 (1979); In re Joseph, 44 Colo. App. 128, 613 P.2d 344 (1980); Wyatt v. United Airlines, 638 P.2d 812 (Colo. App. 1981); In re Norton, 640 P.2d 254 (Colo. App. 1981); People in Interest of W.M., 643 P.2d 794 (Colo. App. 1982); United Bank of Denver Nat'l Ass'n v. Pierson, 661 P.2d 1191 (Colo. App. 1982); Smith v. Colo. Dept. of Rev., 661 P.2d 1192 (Colo. App. 1982); Schoonover v. Hedlund Abstract Co. Inc., 727 P.2d 408 (Colo. App. 1986); Citicorp Mortg., Inc. v. Younger, 856 P.2d 52 (Colo. App. 1993); Anderson v. Somatogen, Inc., 940 P.2d 1079 (Colo. App. 1996); In re Custody of C.J.S., 37 P.3d 479 (Colo. App. 2001); Yadon v. Lowry, 126 P.3d 332 (Colo. App. 2005). .