Pursuing Powell event from Seward House Museum

[Clarence]

(04-10-2022 01:19 PM)Linda Anderson Wrote:  "Staff from the Seward House Museum, Ford’s Theatre National Historic Site, and the Huntington Library will reflect on Lewis Powell’s part in the Lincoln assassination conspiracy. Using artifacts from their respective collections (Powell’s gun, knife, and other personal effects), each site will discuss how they interpret Powell’s attack against the Seward family on April 14, 1865. This event is taking place on Facebook live, direct link to come."

https://sewardhouse.org/visit/events-cal...2022-04-12

Can anyone tell me when Paine was determined to be Powell?
Thanks
Clarence