NORWALK, Conn. — The former babysitter at the center of an underaged sex scandal involving Michael Kennedy five years ago testified that she never heard Kennedy's cousin, Michael Skakel, joke at a party, "ask me why I killed my neighbor."

The testimony of Marissa Verrochi, the babysitter, contradicts a prosecution witness who testified earlier this week that Skakel made the joke about killing Martha Moxley in 1975 while she, Verrochi and others were at a party at her South Boston home.

Verrochi, who was staying with the witness, Gerrane Ridge, to stay hidden from the media during the scandal, testified that she was never even in the same room as Ridge and Skakel.

Marissa Verrochi, now 24, testified that she met Skakel when she was 15 years old and he was working for Michael Kennedy in energy consortium in Massachusetts. Kennedy died in a skiing accident in Aspen in 1997.

Prosecutors say Skakel killed his 15-year-old neighbor on Oct. 30, 1975, because he was jealous of his brother's relationship with Martha Moxley. Skakel, who was charged with the killing 25 years later, denies any involvement in the crime.

On cross-examination, Prosecutor Jonathan Benedict stayed away from direct references to the Kennedy sex scandal, in which Michael Kennedy, a son of the late Robert F. Kennedy, was once investigated for having sex with Verrochi when she was a minor and the babysitter of his children. Kennedy was never charged.

Benedict did get Verrochi to explain that she and Skakel became very close because he protected her during the scandal.

Ridge, the prosecution witness, testified earlier this week that Verrochi was present at the party in 1997, and that Skakel was there at Verrochi's invitation. Although Ridge says she never met Skakel, she testified she overheard him telling Verrochi and others, "ask me why I killed my neighbor."

There has been testimony that Skakel was forced to wear a sign around his neck with similar wording while he was a resident at Elan, a treatment center for troubled youths in Poland Springs, Maine, in 1978. The heart of the prosecution's case includes testimony from former Elan residents who say Skakel confessed to the killing.

Earlier Thursday, Judge John Kavanewsky conducted an inquiry into whether a juror violated his oath not to discuss the case when he told another juror that he saw Michael Skakel mouth the words "good job" to his cousin, who testified Wednesday that Skakel was at his home watching television that the time police believe Martha Moxley may have been killed.

The male juror, who is a corporate lawyer, was questioned by the judge in open court after an alternate juror reported the incident. The juror admitted that he made the comment.

After polling each of the jurors to see what they had witnessed or heard, Kavanewsky decided not to dismiss the juror.