I'm sure somebody has noticed this before me but the Metadata panel does not show the Capture Date correctly for (some) video files! I have a Panasonic DMC-ZS20 for point and shoot and occasionally record video files. These appear in LR CC 2015 as MTS files but they don't show up in the correct Smart Collections based upon Capture Date even though the Top Label in Grid View containing the video file shows the correct (original) Capture Date. What am I doing wrong? Does anyone have a fix for this? Thanks
This bug has been present in LR for many years, since version 3. Please add your vote and opinion to this bug report in the official Adobe feedback forum: Lightroom: Still inconsistent capture date/time for videos.
Also, see that topic for workarounds.