They used her thumbprint to assess her ID. Since her thumbprint never changes over the years, they simply assume she's the Jennifer of the future.
6 seconds sound clip from the Back to the Future Part II movie soundboard.
You can hear this line at 00:25:21.779 in the Blu-ray version of the movie.
Quote context
[...]
- I am going to put this in the trash.
- McFly, Jennifer Jane Parker, 3793 Oakhurst Street, Hilldale, age 47.
- Forty-seven? That's a hell of a good face-lift.
- What the hell are they doing, Doc?
- What are we gonna say? That we're time travelers? They'd have us committed.
- She's clean. That means we take her home.
- Home? To Hilldale? It'll be dark by the time we get out there.
- That's it. They're taking her home. To your future home!
[...]
Top rated lines from this movie
Memorable lines from Back to the Future Part II (1989), featuring audio clips and sfx.
Actors: Michael J. Fox (Marty McFly), Christopher Lloyd (Dr. Emmett Brown), Lea Thompson (Lorraine Baines-McFly), Thomas F. Wilson (Biff Tannen)
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