There are different possibilities.
If you only want to apply the same crop to all your pictures simply use
Irfanview.
If you need "mostly" the same crop but want to fine-tune it, try
JPEGCrops.
For more involved detection, while may be better (one-click) tools available now, I have used
Imagemagick together with the
Autotrim script in the past.
Also, you can try to write a "crop" action for Photoshop or Gimp.