In all the Oregon Tiger Beetle populations I’ve observed, I’ve seen pairs mating.

During mating and mate guarding, the male grips the female between the thorax and elytra with his jaws (4 and 6).

1, 3 sclerotized penis sheath, aedeagus, visible 1 Cropped close up
3 Cropped close up
2 movie, mating, followed by the male quickly withdrawing the aedeagus.
30 frames per second.		 Slow-motion version
one frame per two seconds

Note that the aedeagus swings through 180˚, then withdraws into the male’s abdomen. According to Pearson, et. al., the aedeagus also rotates 90˚ on its axis when withdrawing into the abdomen.
Figure 2.6, external male reproductive system,
A Field Guide to the Tiger Beetles of the United States and Canada, Pearson, et. al.
4 male gripping the female as during mating and mate guarding
5 female laying eggs in the sand 5 Cropped close up
6 male mate guarding while the female lays
Figure 2.7, external female reproductive system,
A Field Guide to the Tiger Beetles of the United States and Canada, Pearson, et. al.