will uphold the decision only if it is supported by substantial evidence. Id. “Substantial evidence on the record as a whole is evidence demonstrating the reasonableness of an agency’s decision, and we neither reweigh the evidence nor replace the fact finder’s conclusions with our own.” DeWitt v. Rent-A-Center, Inc., 2009-NMSC-032, ¶ 12, 146 N.M. 453, 212 P.3d 341 (citation omitted). IY. DISCUSSION A. Constitutional Claims {19} The constitutionality of the PRC’s rulings present this Court with a question of law, which we review de novo. See Archuleta v. Santa Fe Police Dep’t, 2005-NMSC-006, ¶ 19, 137 N.M. 161, 108 P.3d 1019 (applying de novo standard of review to due process violations); U S West Commc’ns, Inc. v. N.M. State Corp. Comm’n, 1999-NMSC-016, ¶ 15, 127 N.M. 254, 980 P.2d 37 (<HOLDING>); U S West Commc’ns, Inc. v. N.M. State Corp.
holding that whether statements are testimonial is a legal issue subject to de novo review holding statutory interpretation is subject to de novo review holding that the constitutional rights in a termination proceeding  are derived from the due process clause of the fourteenth amendment of the united states constitution and not the sixth amendment holding that once defendant made appearance in cause he is entitled to notice of trial setting as matter of due process under fourteenth amendment to the united states constitution holding that an agencys rulings with respect to whether a party was afforded the process it is due under the fourteenth amendment to the united states constitution are subject to de novo review