David... Thanks. Here is what I found so far:

Co. I, 6th Kansas Cavalry underwent three dramatic changes. Actually, Burke's description (which ends prematurely) is acurate if you check it closely. First the 6th Kansas Cavalry was raised as three infantry companies under William Judson at Fort Scott, Bourbon County (A,B,C) and additional companies were raised by September 1861. One company identified itself as Company I, but the designation was changed. Then during the consolidation of Lane's Brigade, Captain Van Sickle's Independent Company of Scouts, formerly of Montgomery's Third Kansas Regiment became Company I, 6th Kansas Cavalry. However in 1862, this company was found to have been mustered irregularly, and was mustered out; leaving no Company I, L or M, which was needed to complete the regiment. In 1863 officers were detached with permission of Governor Thomas Carney to recruit the regiment to full strength. Company I was recruited around Westport, Missouri under Captain John T. Blake, a resident of Independence, Missouri. It appears from the roster, that many of the men were from Jackson County, Missouri, traditionally a hotbed of secessionism. Also, this late in the war the fever of patriotism had died down.

The rosters do show a significant number of men being courtmartialed and dishonorably discharged. Those tried and found guilty on September 4, 1865 from Co. I, in St. Louis were:

Private William Armstrong, from Shawnee, Kansas
Private Thomas Bernard
Private James Gillseece
Private Lorenzo Hoover
Private Daniel Murphy
Private Jasper N. Smith, Twin Springs, Kansas
Private Samuel Bucher, Westport, Missouri
Private James Murphy, Pleasant Hill, Missouri
Private Edward F. Smally, Twin Springs, Kansas

Private James McGuire was tried by courtmartial and dishonorably discharged on August 5, 1865 at Columbus, Ohio.

Private William H. Renick, Westport, Missouri, was tried by courtmartial and dishonorably discharged on September 5, 1865 at DuVall's Bluff, Arkansas.

That makes 9 men being tried and found guilty on the same date, which was several weeks past the 6th Kansas Cavalry being mustered out.

Here is what I suggest. Find microfilm of the Missouri Republican and Missouri Democrat from September 1, 1865 to September 15, 1865 and look for articles on Courtmartials in St. Louis. I checked and I don't have copies of this paper past July 1865.

Try to locate War Department, Special Orders #474. Private Daniel Murphy was sentenced under this order, which would probably cover the other nine men in St. Louis.

Check the town histories of Twin Springs, Kansas; Pleasant Hill, Missouri; Shawnee, Kansas or Westport, Missouri to see if mention of any of the men/families are there.

Look up John T. Black, Independence, Missouri. He mustered out in 1866 and may have left documentation on his company.

You could order the military records (make sure you note "please include all court-martial records") for Private Daniel Murphy from the National Archives. Most likely the Special Orders might be included. Or you could order Captain Black's military records.

See if these ideas would help.

Thanks,
Howard Mann