In the absence of or in absence of?

English as a Second Language English Vocabulary, Grammar and Idioms
1

To me, it should be in the absence of. Is the other which I often see in legal diction acceptable and grammatical in such contexts?

2

I am told that the phrase without the definite article is AmE.

3

I would generally use the phrase with the article, but would accept the form as written in the original message here as being an alternative.
I don’t know whether it’s specifically AmE, though. It may be the case.

4

Yes, thanks.