An Item to Prevent Crits

I've found that lately, most adc's will rush a IE and maybe even a static shiv resulting in basically a 50% crit rate. ADCs are supposed to be heavy sustained damage, however; with high attack speed and crit damage, they almost seem bursty. What if a new defensive item was made that would prevent crits.

If it had an active skill, it would prevent crits for X amount of time on targeted champion.

If it had a passive skill, it could decrease the chance of being critted by X amount. Ex. When enemy attacks you, instead of a 50% chance, they now have 25% chance.

I'm pretty sure this would be an OP item, especially if a tanky support had it (would almost be like a second exhaust if it was an active). However, if it was a passive, it might not be as bad.