A ballistic barrier, comprising: a first modular unit comprising: a first frame and a first protective panel coupled to the first frame, the first protective panel having a first side that faces the first frame and a second side that is opposite the first side, the second side including a ballistic resistant material configured to withstand a ballistic projectile fired toward the barrier; and a member coupled to at least one of the frame and the protective panel, the member extending out from the first side of the protective panel, the member defining a gap between the first side of the protective panel and a first surface of the member, wherein the gap defines an angle measured from the first side of the protective panel to the first surface of the member, and the gap is configured to receive at least a portion of a protective panel of a second modular unit of the ballistic barrier, and a second modular unit comprising: a second frame and a second protective panel coupled to the second frame, the second protective panel having a first side that faces the second frame and a second side that is opposite the first side of the second protective panel, the second side of the second protective panel including a ballistic resistant material configured to withstand a ballistic projectile fired toward the barrier; and characterised in that the second protective panel abuts the first protective panel thereby defining a first point of contact between the first and second modular units, and the second protective panel simultaneously abuts the first surface of the member thereby defining a second point of contact between the first and second modular units. a first modular unit comprising: a first frame and a first protective panel coupled to the first frame, the first protective panel having a first side that faces the first frame and a second side that is opposite the first side, the second side including a ballistic resistant material configured to withstand a ballistic projectile fired toward the barrier; and a member coupled to at least one of the frame and the protective panel, the member extending out from the first side of the protective panel, the member defining a gap between the first side of the protective panel and a first surface of the member, a first frame and a first protective panel coupled to the first frame, the first protective panel having a first side that faces the first frame and a second side that is opposite the first side, the second side including a ballistic resistant material configured to withstand a ballistic projectile fired toward the barrier; and a member coupled to at least one of the frame and the protective panel, the member extending out from the first side of the protective panel, the member defining a gap between the first side of the protective panel and a first surface of the member, wherein the gap defines an angle measured from the first side of the protective panel to the first surface of the member, and the gap is configured to receive at least a portion of a protective panel of a second modular unit of the ballistic barrier, and a second modular unit comprising: a second frame and a second protective panel coupled to the second frame, the second protective panel having a first side that faces the second frame and a second side that is opposite the first side of the second protective panel, the second side of the second protective panel including a ballistic resistant material configured to withstand a ballistic projectile fired toward the barrier; and characterised in that the second protective panel abuts the first protective panel thereby defining a first point of contact between the first and second modular units, and the second protective panel simultaneously abuts the first surface of the member thereby defining a second point of contact between the first and second modular units. a second frame and a second protective panel coupled to the second frame, the second protective panel having a first side that faces the second frame and a second side that is opposite the first side of the second protective panel, the second side of the second protective panel including a ballistic resistant material configured to withstand a ballistic projectile fired toward the barrier; and characterised in that the second protective panel abuts the first protective panel thereby defining a first point of contact between the first and second modular units, and the second protective panel simultaneously abuts the first surface of the member thereby defining a second point of contact between the first and second modular units.