Law & Order is no longer available for purchase, but if you bought it direct
from TellTale, you should be able to redownload it.
https://telltale.com/support/article/why-is-law-order-legacies-is-no-longer-available-/If you purchased the games, the general procedure for re-download is
1. Go to
https://www.telltale.com/ and sign into your Telltale account.
2. Go to your profile page and select the My Games tab.
3. Click on the name of your game to access the download page.
Note that they have changed their website from telltalegames.com to telltale.com
so you will be automatically forwarded to their new homepage if you use an old link.