We at EFF were really honored when he signed on to our brief on GPS tracking in U.S. v. Jones in 2011:<p><a href="https://www.eff.org/files/filenode/US_v_Jones/10-1259bsac_eff_cdt_amicus.pdf" rel="nofollow">https://www.eff.org/files/filenode/US_v_Jones/10-1259bsac_ef...</a><p>(The position advocated by that brief was accepted by a minority of the court; the majority ruled in our favor for a different reason, based on the physical trespass against a person's car when attaching a tracking device to it.)