Nearly 6,000 pedestrians were killed in the U.S. in 2017, according to a new study, and some experts have linked the accidents to distractions such as smartphones and marijuana. Richard Retting, the director of safety for Sam Schwartz Consulting and author of the report, said: “People outside cars are dying at levels we haven’t seen in 25 years.” It’s not certain why so many more people are dying outside cars than a few years ago, but the report noted that, in the seven states that legalized pot for recreational purposes, as well as the District of Columbia, pedestrian deaths spiked 16.4 percent in the first half of 2017, while deaths fell elsewhere. “We’re not making a definitive link here and saying this is an ‘aha’ moment, but it’s a source of concern and we think greater attention needs to be paid to this issue,” Retting said. Rebecca Lindland, a Kelley Blue Book auto analyst, said pedestrians distracted by smartphones could be to blame. “At some point in time people both behind the wheel and walking in the street have to take responsibility for their behavior and put down the phone,” she said.