I am looking for a plot device to commit a murder. The murder happens in the summer, in a public park, on camera. It is a jogger.?

A few people acting as dogwalkers; one releases the trained dog(s) thath then run(s) to the other trainer, tripping up the jogger on the way (cue a trailing leash) so (s)he falls and breaks his/her neck.

No direct contact between the killers and the victim, a relatively easy to stage 'accident'. You sometimes see dogwalkers with those multi strand leashes, which would make the tripping part easier. Preparation would be key.

A future technology that the murderer can wear that will block his image from the camera, like a cloak of some sort. It's not exactly new sci-fi that can't be found in other books. Maybe u can add something to it to make it more unique.

The guy is invisible and trips her and she falls in the bushes where he kills her, making it seem like she hit her head. Or maybe he poisons her by shooting her up with a poison that can't be easily detected. Future tech where the murderer comes from can combat this invisibility device.

A jogger, sips on his water bottle and continues jogging. A few minutes later, clutches his chest and falls over in front of the camera and many witnesses. Several people rush to his aid, but one witness sees someone switch water bottles.

Apitoxin? If the jogger is allergic to bees, a strong dose of apitoxin (the venom bees carry) could kill them. I don't know how much apitoxin, but it can be administered by needle. It would just show up as bee toxin in an autopsy.