Mexico City - On Saturday, Mexico went from a mostly closed system of written proceedings to one that opens up trials to the public and grants people accused of a crime more rights.

The oral hearings are the final stage of nationwide reforms that were passed as a constitutional amendment by Mexico's congress back in 2008 that seek to change every step of the criminal justice system, from the time police arrive at a crime scene to the moment a sentence is imposed.

Its goal is ambitious — to combat the country's high rate of impunity, and increase the public's faith in legal institutions.

Mexico's old judicial system was outdated and ineffective. Trials for misdemeanor crimes dragged on for years and the accused wasn't always guaranteed access to a proper defense. Judges made rulings based off arguments and evidence submitted in writing, typically in an office space that wasn't set up to receive the public.

The new system inserts accountability into the process. Trials now require oral arguments before a judge and are open to the public in newly constructed US-style courtrooms. The burden of proof falls on the government, meaning the prosecution must convince a judge that the person accused of a crime is truly guilty. Proof must come in the form of witnesses and scientific evidence.

"This is an historic moment for the country," President Enrique Peña Nieto said during a ceremony late Friday marking the change. He called it "the most transcendent juridical transformation of the last 100 years."

Some 300,000 police officers have undergone training for their roles in the new system, learning how to better preserve a crime scene and how to testify in court. The same goes for lawyers and judges.

The system also incorporates non-prison alternative rulings, such as mediation and reparations, in an effort to reduce the country's swollen prison populations.

If successful, judicial reform could make for a safer, more prosperous Mexico. It will help Mexico strengthen its rule of law, which could result in building greater trust with the United States. That would allow for deeper binational collaboration on shared issues such as drug trafficking or trade. It could result in the U.S. lifting travel warnings in Mexico, making Americans more comfortable about traveling here and businesses more confident about investing here.