In mid July of 1863 General Thomas Ewing began ordering the arrest of the relatives of known Missouri Partisan Rangers in an attempt to deny the partisans their base of support in Missouri. The majority of these prisoners were female relatives of the partisans, such as Bill Anderson, John McCorkle, Riley Crawford and Kerr.
"It is an utter impossibility to rid the country of these pestilent outlaws, so long as their families remain...One of the greatest difficulties the military authorities have to encounter, is the constant information that the families of the bushwhackers give of every movement the troops make...With the aid of these spies, dotted all over the country and living in the perfect security, a hundred bushwhackers may defy the efforts of five hundred solders to exterminate them
From the Kansas City Daily Journal of Commerce regarding the orders from Ewing
The women were held in a adhoc jail in a three story uilding in Kansas City at 1409 Grand Avenue, known as the Longhorn Store & Tavern owned by the wife of George Caleb Bingham .On August 3rd, 1863 the building collasped, killing four women and injuring many others.
This is where it gets heated. Some southern sources claim that the Federals purposely compromised the building to murder the women, federal sources admit that work was being done that did compromise the building but it was not done on purpose. Southern sources claim Union soldiers were heard while drunk laughing and claiming that the act had been done on purpose, Federals sources deny this.
In any event the Raid on Lawrence is often justified by the Jail Collaspe as a reason.
Links: (This still a "hot button" issue so some views are slanted)