I don't think there's a single off field incident in Peter's past. The risk in this trade seems pretty small to me. Peter's on filed stuff doesn't seem worse than Aaron Donald's and he turned out OK. (In 2016 Donald drew an unsportsmanlike penalty for throwing a flag at an official and was fined $24,309 for it, got fined $18,231 for unnecessary roughness, got fined $12,154 for an unsportsmanlike penalty earlier in the season. In total AD was fined over $81,000 in 2016 and was kicked out of 1 game.)
AlbaNY_Ram