The 27-year-old, who will join Wasps for the start of next season from Hurricanes, is eligible to play for England through his parents but the decision for him to represent the Red Rose has drawn plenty of criticism.
New Zealand Rugby have been the main critics questioning why there is a need for England to select someone who has never plied his trade in the country before.
However, Jones says he is not bothered by their ire, saying he picks good players who are able to represent England.
"It's my responsibility to pick England-qualified players. I get a list of England-qualified players, then I pick the best ones. I don't decide the regulations."
Of Shields, Jones said: "He's a good, hard-working player, he's an excellent player and he plays for the best team in the southern hemisphere. He's a considerable influence in that team, a team that has a lot of skill. He is a hard-working, gritty player and is a great back-up for Chris Robshaw for us."