You can justify, from a political standpoint, any type of violence you want to use.
I think violence is part of the struggle against oppression. If something bad happens to these people [animal researchers], it will discourage others. It is inevitable that violence will be used in the struggle and that it will be effective.
Violence has been a necessary component of every serious liberation struggle...Violence is not the only path to liberation, but likely an indispensable one...the Press Office would like to be clear on this matter: we support all the liberationists from the graffiti artists and ALF liberator to the Animal Rights Militia, Justice Department and Revolutionary Cells.
I think Dario Ringach is a poster boy for the concept that the use of force or the threat of force is an effective means to stop people who abuse animals," "No strictly peaceful movement has succeeded in liberation," "I think the animal rights movement has been restrained in its use of force, mostly because people in the struggle are often people of privilege who aren't willing to risk losing that privilege.
If you had to hurt somebody or intimidate them or kill them, it would be morally justifiable.