"Girl in a Bird Cage" is a 1962 episode of Armchair Theatre starring Janet Munro.
[1][2] Judy Parfitt played a lesbian character which was rare for the time.
[3] A girl is jailed for stabbing the man she loved.
"More of a dramatic documentary than anything and as such was spoiled by melodrama and coincidence.
But it was very capably produced and very nicely acted.