A non-hormonal, reversible and non-toxic male birth control could be a step closer, with scientists successfully targeting a protein that's crucial in making fertile sperm. Knocking this protein out for a period of time would give men control over their protection window, much like oral…
It is pretty easy to tamper with a condom in invisible ways, from poking holes or letting it expire, to stealthing. Hell, you can even cook the condom at low heat for a while in its package and you will cause significant structural damage to it, without even bruising most packaging.
Even a freshly bought condom and a little sleight of hand can go a long way into tampering. No birth control is trust free.