Michael Lacy and James Harbic, for appellant C.B.
Matthew Gourlay, for appellant A.C.
Jessica Smith Joy, for respondent Crown.
The judgment of the court was delivered by
[ 1] WATT J.A.: — D.P. and G.D. were friends. They were 16,
attended high school and lived at home with their parents with
whom each was in conflict. About truancy. And about drinking
and drug use.
[ 2] C.B. was 20. She also lived at home with her parents. She
had a boyfriend, A.C. He was 31. Drugs and alcohol were readily
available when C.B. and A.C. were together.
[ 3] D.P. and G.D. spent a lot of time at C.B.’s house. School time.
Weekend time. Drinking and smoking. Alcohol and marijuana.
 One evening in May a few years ago, D.P. went to C.B.’s
house. A.C. was there. D.P. smoked some marijuana and drank
some alcohol. D.P. claimed that something else happened during
this visit, something that took place without her consent: a sexual
assault on her by both C.B. and A.C.
[ 5] A few days later, D.P. returned to C.B.’s home. This time,
she brought her friend, G.D., with her. A.C. was there. The same
thing happened again. Marijuana. Alcohol. And a sexual assault.
This time the victim was not D.P., but her friend, G.D.
[ 6] C.B. and A.C. were jointly charged with several offences in
relation to both D.P. and G.D. Assault. Sexual assault. Unlawful
[ 7] After a joint trial before a judge of the Ontario Court of
Justice, C.B. and A.C. (the appellants) were convicted on all
counts. Each appeals conviction. C.B. also appeals sentence.
[ 8] The reasons that follow explain why I have decided that
errors in the course of the trial require that the convictions be set
aside and a new trial ordered. In these circumstances, I do not
reach the sentence appeal by C.B.
The Background Facts
[ 9] The grounds of appeal advanced do not require a detailed
recital of the circumstances of the offences of which the appel-
lants were convicted. A brief outline is sufficient.
The principals and their relationship
[ 10] D.P. and G.D. were friends. Each was 16 and at odds with
her parents about truancy, drinking and drug use. Each appears
to have chafed at parental discipline.