Yes, bobcats eat deer. Despite the bobcat’s diet being dominated by rabbits or hares (lagomorphs) over much of the areas where bobcats are seen they also eat rodents and deer which are important sources of food (and many other animals e.g. porcupines and skunks). Prey availability depends, as usual, on the season and the location.
For instance, D.E. Towel in his Oregon State University PhD dissertation: Resource partitioning by bobcats and coyotes in a coniferous forest, reported that the remains of black-tailed deer were found in their scats. He was referring to the bobcat’s summer diet in Oregon’s western Cascades. Although as expected the snowshoe hare made up 28 percent of their diet. Other prey of Oregon’s bobcat as reported in 1986 were: beaver, pocket gopher and passerine birds.
The bobcat is a serious predator of fawns as reported by several scientists in their studies (RF Labisky, MC Boulay, FB Barick, MB Epstein, GA Feldhamer and RL Joyner). In America’s southeast, except for Florida, adult deer don’t figure substantially in the bobcat’s diet.
FREQUENCY OF OCCURRENCE OF PREY ITEMS IN THE DIETS OF BOBCATS (PERCENTAGE OF SAMPLES): White-tailed deer: Florida (2.4), Michigan (26.7) and Washington (12.1) – these were stomach contents. If you’d like precise references that I used for this post please ask in a comment. Thanks.