This will have to happen. In a diverse, pluralist society, the law should apply equally to everyone. We should avoid granting legal exemptions to specific groups, particularly where public or individual safety is concerned.
Harmful and illegal practices such as forced marriage, child marriage and FGM must be confronted consistently, regardless of the cultural, religious, or ethnic background of those involved. While these are illegal in the UK, there is a concern that, authorities are hesitant to enforce the law as robustly as they should for fear of being accused of racism, discrimination, or cultural insensitivity.
Equal treatment under the law requires the same standards to be applied to everyone, consistently.
We do not generally permit people to disregard public norms or legal restrictions simply because a particular practice is central to their personal identity. We wouldn't allow a naturist to ignore public decency laws because their lifestyle promotes nudity. We wouldn’t let someone drive on the wrong side of the road because it’s their cultural tradition or let someone break noise regulations because they are Metalheads.
Sikhs are not a trouble making community at all. They must be so hurt, worried and angry at the Digwa family. Poor move by the way of the Digwa granny to comment in a somewhat self pitying manner justifying that Jasbir Digwa did what any loving mother would do 
Kirpans haven't to date been a public health concern as such, as no trouble has been had so far. But the expert witness explained that younger Sikh carry more dingoes venisons of these knives and that's a concern. Now that the public is aware that Siks carry potentially dangerous knives, a random thug might well try and get hold of it to attack people. Indeed Vickrum Digwa told the police (falsely) he was scared that Henry would get hold of his Kirpan and use it against him.
This tragedy was preventable. One reason this tragedy happened is that in an attempt to reduce racism in society (good) any accusation of racism now trumps other more urgent issues. This is not the way to go about cohesion between diverse communities. A common rule of law and cultural expectations from all is what's needed.
It is interesting to note that the mum, Jasbir Digwa never worked in the UK so likely never really integrated in British society. This also is a concern and goodness knows what that family's home life was like for the sons to turn out the way they did. They clearly had a special interest in ceremonial knives.