Murder at Wakehurst / Alyssa Maxwell.

Enhanced descriptions from Syndetics:

In the autumnal chill of Newport, Rhode Island, at the close of the nineteenth century, journalist Emma Cross discovers an instance of cold-blooded murder on the grounds of a mansion...

Following the death of her uncle, Cornelius Vanderbilt, in September 1899, a somber Emma is in no mood for one of Newport's extravagant parties. But to keep Vanderbilt's reckless son Neily out of trouble, she agrees to accompany him to an Elizabethan fete on the lavish grounds of Wakehurst, the Ochre Point "cottage" modeled after an English palace, owned by Anglophile James Van Alen.

Held in Wakehurst's English-style gardens, the festivities will include a swordplay demonstration, an archery competition, scenes from Shakespeare's plays, and even a joust. As Emma wanders the grounds distracted by grief, she overhears a fierce argument between a man and a woman behind a tall hedge. As the joust begins, she's drawn by the barking of Van Alen's dogs and finds a man on the ground, an arrow through his chest.

The victim is one of the 400's most influential members, Judge Clayton Schuyler. Could one of the countless criminals he'd imprisoned over the years have returned to seek revenge--or could one of his own family members have targeted him? With the help of her beau Derrick Andrews and Detective Jesse Whyte, Emma begins to learn the judge was not the straight arrow he appeared to be. As their investigation leads them in ever-widening circles, Emma will have to score a bull's eye to stop the killer from taking another life...