[metmom]

A dangerous pit bull seized from a dog-fighting ring in Ontario, Canada, scheduled to be euthanized, instead has been “saved” by pit bull promoters and is on his way to K-9 police dog training

WHY in God's name?

Put the thing down.

There's got to be plenty of other dogs that would be more suitable for police K-9 work than a four legged death machine.

[Norski]

The site referenced is worth checking daily if one can stand it. As for why -

Here is a five part series which I believe give some answers. It is a pdf.

My opinion is 1) Money and 2) the entities in control of the persons pushing pit bulls and other dangerous dogs enjoy the results of their efforts.

https://www.dogsbite.org/pdf/08-13-16-la-presse-five-part-series-pit-bulls-vet-report.pdf