[AmishDude]

Simply having worked with a witness is not a basis for an automatic disqualification.

But you said it was. You said they could have simply objected for cause and that was that. Which is it?

They didn't want him on the jury. It was clear they were grilling him (see the linked Slate article) and decided to give up since he was saying all the right things.

[lugsoul]

Since you so clearly don't know what you are talking about, let's review:

A jury is first "qualified" by the court as to certain relationships, including with the parties. Some people aren't eligible to serve - for example, those with a financial interest in the outcome.

Of those who are eligible to serve, some can be stricken "for cause," - not necessitating the use of a peremptory strike. I have little doubt they could've gotten rid of this guy for cause. There is no indication they tried. This usually happens at sidebar after that juror is questioned.

If you have anything else to say on this topic, please try to have some idea what you are talking about.