State ex rel. Phelps v. McClelland (Slip Opinion), 2020 Ohio 831

In 1993 Larry Phelps and Laura Phelps were indicted, including an aggravated-murder count with death-penalty specifications.
Trial court found the state could not compel Laura to testify because she was Phelps's common-law wife; the prosecutor and Laura then agreed she would waive privilege if the prosecutor deleted the death-penalty specification against Larry.
The court accepted the agreement; Laura testified at trial, but the jury nonetheless returned verdicts on death-penalty specifications; Phelps was convicted and sentenced to life.
Phelps’s 1996 direct appeal did not raise any claim regarding the prosecutor’s agreement with Laura; convictions were affirmed.
In 2017 Phelps moved in the trial court for specific enforcement (a new trial) alleging the state breached the agreement; the trial court denied the motion and the court of appeals affirmed based on res judicata.
In 2018 Phelps filed a mandamus complaint asking the common-pleas judge to enforce the agreement; the court of appeals granted summary judgment to the judge, holding Phelps had an adequate remedy at law and that res judicata barred the claim. The Ohio Supreme Court affirmed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Availability of mandamus (adequate remedy at law)	Phelps: mandamus is proper to enforce the prosecutor–Laura agreement and protect rights.	Judge/State: Phelps had an adequate remedy (motion to specifically enforce; direct appeal) and already used it in 2017.	Held: No mandamus — Phelps had an adequate legal remedy and invoked it.
Res judicata/bar to relitigation	Phelps: claim not ripe for earlier appeal; merits justify relief now.	Judge/State: Claim could have been raised on direct appeal and was litigated in 2017; res judicata bars rehearing.	Held: Claim barred by res judicata; cannot relitigate same issue.

State ex rel. Manley v. Walsh, 142 Ohio St.3d 384 (Ohio 2014) (summary-judgment review in mandamus actions is de novo)
Smith v. McBride, 130 Ohio St.3d 51 (Ohio 2011) (Civ.R. 56 summary-judgment standard)
State ex rel. Love v. O’Donnell, 150 Ohio St.3d 378 (Ohio 2017) (mandamus elements: clear right, clear duty, no adequate remedy)
State ex rel. Duran v. Kelsey, 106 Ohio St.3d 58 (Ohio 2005) (adequate remedy exists by motion to enforce agreement before sentencing court)
State ex rel. Seikbert v. Wilkinson, 69 Ohio St.3d 489 (Ohio 1994) (analyzing alleged breach of plea agreement and enforcement remedy)
State ex rel. Sampson v. Parrott, 82 Ohio St.3d 92 (Ohio 1998) (mandamus will not lie after a plain and adequate remedy at law was unsuccessfully invoked)
State ex rel. Robinson v. Huron Cty. Court of Common Pleas, 143 Ohio St.3d 127 (Ohio 2015) (res judicata bars claims that were or could have been litigated in a first action)