Below: Gotham City Cops, if they existed, would be quite outraged at their portrayal here (or embarrassed at being exposed).
Didn't the Batman milieu begin originally with this interpretation of the institution of urban law enforcement? Corruption has been a peripheral portrait of cops in the Batman comics since the latter days of Jenette Kahn's days at DC Comics, when she allowed Frank Miller do the original Dark Knight mini-series.
In contrast to the back-and-forth integrity of Gotham cops in the Batman books over the decades, it is not so with Gordon. He has always been shown to be a "honest cop" even from the beginning (though, depending on the trend of the times, he may be shown to be quite flawed as a person).
In general though, we can see that Gordon has been corrupted by Batman. Except for those time periods when Batman is shown to be within the institution of Gotham law enforcement (like the Adam West Batman TV Show, for example.) Batman is an exterior agent, his "own police force" and not held to, nor holding to whatever it is that guides police officers. Batman is quite willing to corrupt the Commissioner in order to further his own aims and to access the information he wants.
See another page from the book
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Catwoman Cover Art by Dustin Nguyen from Detective Comics #845
Catwoman page by Dustin Nguyen from Detective Comics #845
Catwoman #1 "The New 52" edition - cover by Guillem March
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Catwoman Dark End of the Street Page 1
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