Just buy some special ink jet printer ink that conducts an electrical charge. Now to just match up all the fingerprints stolen from the IRS to the actual person’s iPhone. No gonna happen. Cops might like the idea. Fingerprints are not protected  from non-consenting searches.

http://www.wzzm13.com/tech/personal-tech/fooling-a-fingerprint-sensor-is-easier-than-you-think/74764057

http://www.defenseone.com/technology/2016/03/so-thumbprint-thing-your-phone-useless-now/126523/