Looking on the internet deeply has found these results:

in each case is the most popular phrase on the web.

in each cases 133,800 results on the web	in each case 137,100,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
The homeowners in each case were killed humanely. The homeowners in each case were killed humanely. But in each case, the executive branch made the change. But in each case, the more expensive jewelry was left untouched. The report recommends the second option in each case. An assailant was killed in each case? No clinically significant pharmacokinetic interactions were found in each case. An assailant was killed in each case?	But in each case, the executive branch made the change. For practical reasons the person responsible for making the declaration must be clearly identified in each case. limit for implementation of its decision. The Commission shall in each case lay down the time Full justification will be required in each case. We've done heat scans of some of the cemeteries and, in each case, only a handful of Cybermen have so far emerged. Family members reported small personal effects missing in each case. The homeowners in each case were killed humanely.

in each cases

133,800 results on the web

in each case

137,100,000 results on the web

More popular!

The homeowners in each case were killed humanely.
The homeowners in each case were killed humanely.
But in each case, the executive branch made the change.
But in each case, the more expensive jewelry was left untouched.
The report recommends the second option in each case.
An assailant was killed in each case?
No clinically significant pharmacokinetic interactions were found in each case.
An assailant was killed in each case?

But in each case, the executive branch made the change.
For practical reasons the person responsible for making the declaration must be clearly identified in each case.
limit for implementation of its decision.
The Commission shall in each case lay down the time
Full justification will be required in each case.
We've done heat scans of some of the cemeteries and, in each case, only a handful of Cybermen have so far emerged.
Family members reported small personal effects missing in each case.
The homeowners in each case were killed humanely.