"You'll always just be 'Derek' to me."
Little is known about Gordinski's personal life, including how he became a Chicago police officer. At one point during his years as a beat cop, he arrested Derek Morgan when the agent-to-be and some local hoodlums, one of them Rodney Harris, got involved in a fistfight that left Rodney suffering from a lasting head wound. After that, he spent years antagonizing Morgan, arresting him for whatever he could pin on him. Sometime prior to "Profiler, Profiled", he became a full-fledged detective.
Gordinski returns in Morgan's life when the agent comes to visit his mother for her birthday. He arrests Morgan, whom he suspects to be behind the murders of three young boys. Throughout the episode, Gordinski is completely confident that Morgan was behind the murders, pointing out to the BAU that Morgan was very friendly towards young teens, is the only person who ever visits the first victim's grave (doing so whenever he is in Chicago), how he would often call the CPD for updates on the investigation, and his past criminal record, all of which fit the profile Gideon had supplied Gordinski with. When the BAU begins to consider Carl Buford, the owner of a community center, as a suspect, the detective is quick to defend Carl. However, when Morgan evades him and manages to wrangle an inadvertent confession out of Carl, Gordinski makes the arrest. He later apologizes to Morgan for the trouble he caused him.
"I made assumptions about who [Buford's victims] were, why they did what they did. I'm sorry."
Two years prior to Restoration, Gordinski was promoted to the rank of Captain. When two middle-aged men are beaten to death, he calls in the BAU to investigate the case. Gordinski assists in the investigation and ultimately oversees the arrest of the unsub, Rodney Harris, who was molested by Carl years ago. Afterwards, the officer approaches Morgan, states that he had made a promise to put away the criminals the moment he became a cop. He then admits that he didn't live up to his promise, always antagonizing innocent victims like Morgan and being acquainted to closet criminals like Carl, and Gordinski then tells Morgan that he is truly sorry. By the end of the episode, he and Morgan hold a live press conference about Rodney's arrest, which ultimately leads to Carl's murder at the hands of several other prison inmates.
- Gordinski is the third of four police officers to appear more than once in the show's history. The others are:
- Detective Walker, who appeared in the Season Three episode Penelope, then reappeared in the Season Five episode Nameless, Faceless.
- Owen Kim, who appeared in the Season One episode Somebody's Watching as a Los Angeles detective, then reappeared in the Season Five episode The Performer as a lieutenant.
- Detective Sam Ogilvie, who appeared in the Season Eight episode The Apprenticeship, then reappeared in the Season Twelve episode Taboo.
- Skipp Sudduth, the actor who portrays Gordinski, would later go on to direct a Season Three episode of Criminal Minds titled About Face. He is the first of two actors to do this, while the second actor is Jason Alexander, who guest-starred in the Season Four episode Masterpiece and later directed Conflicted, also a Season Four episode.