Pierre Martin is the Chicago Police Department’s (CPD) poster boy for facial recognition. Martin was sentenced this week to 22 years in prison for two armed robberies committed on Chicago trains last year, and he was caught using the department’s $5.4 million facial recognition system, called NeoFace. Martin’s conviction is the first directly resulting from CPD’s use of the system, which was implemented last year following federal funding.

“This case is a great example that these high-tech tools are helping to enhance identification and lead us to defendants that might otherwise evade capture,” said Cook County, Ill.'s State Attorney Anita Alvarez in a statement.

After pulling a gun on a train passenger and taking his smartphone in January 2013, Martin got off the train and his image was captured by surveillance cameras. Another image of Martin was captured in a similar February 2013 robbery. Because Martin had an existing criminal record, CPD’s facial recognition system used those images to identify him. Witnesses later corroborated the match made by the software.

The emergence of facial recognition software has provoked concern amongst privacy and civil liberties groups in recent years, but one American Civil Liberties Union Lawyer told Ars Technica that the organization accepts the technology if it is used narrowly and is not abused.