Emma was in shock and not making a lot of sense but admitted to killing her uncle. Emma must have called Angela, rather than the police, implying she wanted Angela to sort things out. She told Angela that she "didn't mean to kill him" so Angela's first instinct was to protect her daughter by covering up Emma's involvement in the death. Angela would have been better to call Philip to coach Emma in what to say to the police to leave no doubt it was an accident because a clever prosecutor could easily have presented the case as Emma deliberately pushing Jason to his death to facilitate her relationship with Turner Bates. Emma, not being particularly smart, would have been likely to incriminate herself further.