Former Philadelphia Police Inspector Daniel Castro may plead guilty to one of the charges against him in federal court tomorrow morning.

Castro was accused last year of plotting an extortion scheme to shake down a former business partner who owed him money, but in April a trial jury deadlocked on most of the charges. Last month, federal prosecutors announced plans to retry Castro in August.

Castro, 47, has pleaded not guilty to the charges against him, arguing that he committed some crimes because the government entrapped him through the use of an informant. But a filing in U.S. District Court indicates that Castro will enter a change in plea Thursday morning. It is not clear to which charge Castro might be considering pleading guilty.

Sources familiar with the case have speculated that Castro could plead guilty to one of the charges if prosecutors agreed to dismiss other counts against him.

Contact staff writer Allison Steele at 215-854-2641 or asteele@phillynews.com