In the late 1980s, Chris Ochoa was coerced into con­fessing to the rape and murder of the man­ager of a Pizza Hut restau­rant in Austin, Texas.

The police threat­ened Ochoa with the death penalty during the inter­ro­ga­tion, according to law pro­fessor Daniel Medwed, and even pointed to the vein in his arm in which prison offi­cials would admin­ister the lethal injection.

Fright­ened by these tac­tics, Ochoa pleaded guilty and received a life sen­tence. But after lan­guishing in prison for more than a decade, he was exon­er­ated by DNA evidence.

Bar­riers to infor­ma­tion can lead the inno­cent to plead guilty because of a mis­im­pres­sion that the government’s case is much stronger than it actu­ally is,” Medwed told a rapt audi­ence in the Raytheon Amphithe­ater on Thursday after­noon for the 49th annual Robert D. Klein Lec­ture. “Many inno­cent defen­dants have less infor­ma­tion about the case against them than the guilty.”

Medwed is a nation­ally known expert in crim­inal law and a leading scholar in the field of wrongful con­vic­tions. His recent book on the topic—Pros­e­cu­tion Com­plex: America’s Race to Con­vict and Its Impact on the Inno­cent—has received crit­ical acclaim from the likes of New York Times best-​​selling author John Grisham.

Over the course of his hour­long lec­ture, Medwed laid out a con­vincing case for why inno­cent defen­dants plead guilty and well-​​meaning pros­e­cu­tors make deci­sions that con­tribute to wrongful convictions.

He quickly dis­missed the notion of pros­e­cutor as “min­ister of jus­tice,” citing the dif­fi­culty of simul­ta­ne­ously advo­cating for fair­ness and jus­tice for all and rep­re­senting the state in charging and lit­i­gating cases against sus­pected criminals.

This min­ister of jus­tice image is fre­quently a mirage,” he said. “Jug­gling the dual oblig­a­tion is dif­fi­cult and all too often the role of zealous advo­cacy triumphs.”

But why is this the case? According to Medwed, the inherent chal­lenge in rec­on­ciling these roles is exac­er­bated by three fac­tors: cog­ni­tive psy­chology, pro­fes­sional incen­tives, and polit­ical considerations.

Take, for example, cog­ni­tive psy­chology. Cog­ni­tive psy­chol­o­gists, Medwed explained, have long posited that humans are sus­cep­tible to a ten­dency known as “con­fir­ma­tion bias,” in which they develop a theory and then cling to it even in the face of coun­ter­vailing information.

Pros­e­cu­tors are par­tic­u­larly sus­cep­tible. “Once their theory of guilt is val­i­dated by a jury ver­dict of guilt, they tend to become extremely vested in that out­come after­ward,” Medwed explained. “Later on, if they are pre­sented with a post-​​conviction claim of inno­cence, they usu­ally dig in their heals, dis­playing what psy­chol­o­gists call aver­sion to cog­ni­tive dissonance.”

Medwed closed his lec­ture by exam­ining four pro­posals for reform of the plea-​​bargain process: abo­li­tion; trial tax reform; increased pre-​​plea dis­clo­sure; and judi­cial monitoring.

He rejected the idea of abol­ishing plea-​​bargaining, saying, “The crim­inal jus­tice system would grind to a halt without a finan­cial com­mit­ment of epic pro­por­tions to boost the supply of court per­sonnel and facil­i­ties to meet the soaring demands for trials.

And let’s not lose sight of the reality that most crim­inal defen­dants are guilty,” he added.

Nev­er­the­less, Medwed remains opti­mistic that pros­e­cu­tors may one day live up to the exalted title of min­is­ters of jus­tice. “I believe in evo­lu­tion, not rev­o­lu­tion,” he explained, “and a handful of tar­geted, well-​​placed reforms could help pros­e­cu­tors realize this ideal.”

Fol­lowing Medwed’s lec­ture, Stephen W. Director, provost and senior vice pres­i­dent for aca­d­emic affairs, pre­sented him with the Klein Lec­ture­ship medal. The Uni­ver­sity Lec­ture­ship was estab­lished in 1964 and in 1979 was renamed in tribute to the late Robert D. Klein, pro­fessor of math­e­matics, chairman of the Fac­ulty Senate Agenda Com­mittee, and vice chairman of the Fac­ulty Senate.

I feel like I just won the nerd Olympics,” Medwed said.