“I dont advocate anarchy nor vigilantism, but I do believe we have the ability and authority to defend ourselves and assist in the apprehension of a criminal for delivery to legitimate authority for proper judgment”
It stopped being self defense when the owner started chasing the thieves.
Note the conjunction.
Any citizen witnessing a criminal act has the authority to step in and bring the criminals to justice.
That’s not passing judgment, that is simply not aiding and abetting the criminal or condoning its commission by inaction, as advocated by those who seek to establish a police state en lieu of a state respecting liberty.