Frederick Zachs, who is not allowed to associate with felons, filed court papers last week asking permission to communicate with his son, Adam, who is at Cheshire Correctional Institute. His attorneys say prosecutors objected.
The Associated Press left a message with the U.S. Attorney's office Monday.
Frederick Zachs recently served a 6-month prison sentence for helping his son flee to Mexico.
Adam Zachs was convicted in the 1987 shooting death of Peter Carone. He denied the charges, posted a $250,000 bond after sentencing, missed a court date in 1989 and wasn't seen by authorities until the week of his capture last year in Mexico.
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