Burka bans have a direct correlation with anti-Muslim violence.
There is a strong correlation between the introduction of burka bans and an increase in publicly held anti-Islamic beliefs. Members of the public who harbour anti-Muslim sentiment inevitably feel emboldened by the ban and anti-Muslim rhetoric and violence begin to creep into public life.
It is no coincidence that both France and Canada saw an increase in hate crimes against Muslim women once their burka bans had been introduced. In one study that interviewed 35 French Muslims that wore the burka prior to the ban, all 35 reported that the ban had had "significant negative effects" on their lives. 26 of the 35 also reported physical abuse and violence, with assailants pushing them, pulling off their veil, or spitting on them.  A similar pattern was recorded in Quebec. Dozens of assaults against Muslim women are reported at women's centres meetings across Quebec every time they convene. A burka ban fosters an anti-Muslim environment and legitimises the abuse and harassment of Muslim women. It must, therefore, be avoided at all costs.
A burka ban doesn't create an anti-Islamic environment. Public opinion brings about legislation, not the other way around. Our elected officials act according to public opinion. They do not set public opinion. Without the support for a burka ban in the first place, it would not become legislation. In Britain, there is already public support for a burka ban. In a national poll, 57% of Brits said they would back a burka ban. 
[P1] Burka bans lead to an increase in hate crimes against Muslims. [P2] Therefore, a burka ban helps foster an anti-Islamic environment. [P3] Therefore, it should not be enacted.
[Rejecting P2] Legislation does not create the environment, the environment creates the legislation.