The jury of six men and six women so far has deliberated some 18 hours since getting the case on Tuesday.
Skakel, 41, Ethel Kennedy's nephew, is on trial for first-degree murder in the Oct. 30, 1975, slaying of Moxley when they were both 15 and neighbors in Greenwich, Conn.
The judge Thursday afternoon denied a jury request to hear again the second half of the prosecution's summation in which state Attorney Jonathan Benedict, in the words of the victim's mother, Dorothy Moxley, "connected the dots" in the state's basically circumstantial case.
The jury spent much of Wednesday and Thursday listening to a court reporter read back the testimony of several prosecution witnesses dealing basically with Skakel's alibi that he was not in the neighborhood when Moxley was slain.
Skakel claims he went with brothers Rushton Jr. and John to his cousin James Dowdle's home 20 minutes away about 9:30 p.m. and did not return until about 11:15 p.m.
Moxley is believed to have been beaten to death with a golf club at about 10 p.m. that night.
On Wednesday, the jury again heard the testimony of Skakel's older sister, Julie, and her friend, Andrea Shakespeare Renna.
"The first three are clearly testing the alibi," Benedict said after Wednesday's session. "The others are on completely different subjects."
Defense attorney Michael Sherman said the jurors apparently were focusing on 10 p.m. as the time of the slaying, but "that's a guess."
He said the reread "shows how deliberative they are, how careful they are, how structured they are."
The victim's brother, John Moxley, said the questions being asked by the jury "suggest to me they've been trying to build a platform from which they can reach a guilty verdict."
Thomas Skakel, 43, Michael's older brother who was the initial suspect in the case, attended the morning session Wednesday for the first time. He declined to talk to reporters.
In her testimony on May 29, Julie Skakel said that as she was getting ready to drive Renna home that night, she saw a figure run across her family's property, and told police in 1975 she thought it could have been Michael.
On the stand, however, she said she did not believe it was him.
On May 9, Renna testified that she was certain Michael never left with two brothers and the cousin for the cousin's home at about 9:30 p.m. that night.