By Annie Rose Ramos

BALTIMORE (WJZ) — A new app developed in Maryland is helping law enforcement officers investigate crimes.

The app, CSI Checklist, was developed by Thomas Mauriello, a former University of Maryland criminology professor who also worked for the state and federal governments. It tells law enforcement officers things they should be considering, questions to ask, observations to make and resources to call.

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It also includes important guides Mauriello said haven’t always been accessible.

“At three o’clock in the morning or when you’re at the field, it would be embarrassing to pull out a textbook while you’re trying to conduct an investigation,” he said.

But the first moments after a crime can be the most crucial in helping to solve it, which means what the first officers on the scene do or don’t do can greatly affect a case’s outcome, he said.

Mauriello is no stranger to the process of proper investigation; he used to review cases to see what was done improperly and what the weaknesses of the cases were. He said he’s seen too many investigations gone wrong where proper procedures weren’t followed.

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“I have found many times that one person thought the other person did something neither one of them did it and things were lost,” he said.

Those failures affect innocent lives in the process.

“We have people who have spent years in jail who have been exonerated because things went wrong in the investigative process,” Mauriello said.

That was why he spent three years developing the app, which he hopes will help law enforcement agencies across the country.

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“This checklist will give them an opportunity to not miss things,” he said.

Annie Rose Ramos