Remember that the date your ancestor "executed" a document is usually the date he signed it. It is different from a date when the document might have been proved in court by witnesses or recorded in a record book by a clerk. Depending upon the type of document "proof" dates or "recording" dates might be dates on which your ancestor was deceased. Dates of document execution are usually dates when your ancestor was alive.
Dates of execution for criminal offenses may refer to a death date, however (grin!).