I've read that Henry Martin Tanner was never prosecuted for u.c. (unlawful cohabitation, or polygamy) under the Edmunds Anti-Polygamy Act 1882, or the Edmunds-Tucker Act of 1887, but I just found a copy of the Joseph Fish Journal online that says otherwise.
Fish, a resident of Snowflake, Arizona, noted that in 1905:
Senator DeBoise from Idaho has been working up a move against the Mormons and he had brought strong pressure on the officials in northern Arizona to prosecute the polygamists in this action. The officers were compelled to do something and a vast number of witnesses were procured from this section and St. Johns, my wife Adelaide being among the number. So we knew that something was being done and we all that were liable were looking for the office to come and arrest us, but there was but one from this district that left on this account, the others all decided to stay and meet the case, be it what it may. The result of this effort of Senator DeBoise was that there were ten of us arrested in this district.
August 14th, I was arrested this forenoon by Deputy U. S. Marshal Gregory for unlawful cohabitation. As stated, I was looking for this. There were ten of us arrested at the same time. The marshal told me that he would want me the next morning and then went off. Jesse N. Smith's son, Silas S., I suppose, was also indicted but he left the Territory and did not return for several years when the indictment had been set aside. The marshal had arrested several and taken them to St. Johns to give bonds before he arrested me.
August 15th, the marshal had arrested Henry M. Tanner of St. Joseph and had procured a team at the livery stable, and we started for St. Johns were we were to give bonds. We drove to Woodruff where he arrested Levi M. Savage, and he was then taken on with us and we four proceeded on our way to Concho where we put up at Lopez's Hotel (a Mexican establishment. August 16th, we drove over to St. Johns where we soon got our bonds fixed up, G. P. Anderson and James Savage and Tanner also got bonds and we three took dinner with Brother C. P. Anderson after which we all started on our return trip, the Marshal included. We reached Concho at about 4 p.m. where we got supper and then as the weather was so warm we thought we could travel on in the evening, so we continued our journey and traveled a greater part of the night when we stopped to let our animals rest and get a little grass and we lay down on the ground for awhile.
After resting awhile, we went on and reached Woodruff at about 7 am. Here we made another stop to rest our team and I got a little breakfast, when Brother Tanner, the Marshal, and I went on, Brother Savage remaining at Woodruff. The lying down on the ground during a short time in the night gave me a bad cold which lasted me for some time.
October 5th, it will readily be seen by my dates that I have hardly pretended to keep a journal.
I had considerable work in employing lawyers to defend us. President Smith left most of this work for me as I was at Holbrook. I wrote to E. S. Clark of Prescott and asked him what he and R. E. Morrison would take our case for. He said that if they had them all, they would take them for $150 each, that meant $1500 for the ten of us. I reported to President Smith and he said that was rather high and thought that we had better go to trial without lawyers so I reported to S. E. Clark that we could not afford to pay it, but it was not a question of money with them, and stated, "and we both wish to state that our services are at your command, or any of your friends in like circumstances, whether we ever receive any money from you or not. If you feel that you can pay something now and then, all right. If not, this may be taken as an assurance that no demand will ever be made, or any indebtedness claimed, except that arising out of the obligations of mutual friendship and esteem."
On these conditions I engaged them and we were all agreed on this, but some of the St. Johns men were a little afraid of Morrison, fearing that he could not be trusted as he had been an extremely anti-Mormon when he had resided in St. Johns. The ten were: J. W. Brown, --Butler, A. V. Gibbons, D. K. Udall, [R]othlesberger, J. N. Smith, J. W. Smith, H. M. Tanner, L M. Savage, and Joseph Fish. They handled our case in a masterly way and I do not think that there were many who paid the full fee of $150. President Smith did however.
(Bolding added to Henry Tanner's name here; not in original, and I've added a paragraph mark or two.) The journal was provided by Blaine S. Nay on his website, The Nay/McNee Clan. Here is the page about Joseph Fish. Here is a citation for the journal:
Fish, Joseph, Silas Fish, Jesse L. Fish and Elsie Fish Nay. The Life and Times of Joseph Fish Mormon Pioneer: June 27, 1840-December 10, 1926. The Nay/McNee Clan. http://www.three-peaks.net/fish.htm.