A preliminary police report indicated the J. Geils had "died of natural causes".

As leader of The J. Geils Band, the group had 17 songs on the Billboard Hot 100 chart, including 10 top 40-charting hits. The band's biggest single, "Centerfold," spent six weeks at No. 1 and "Freeze-Frame" peaked at No. 4.

Geils formed The J. Geils Band in 1967 with Danny Klein, Magic Dick Salwitz, Stephen Jo Bladd and Peter Wolf while studying at Worcester Polytechnic Institute. They released 11 studio albums before breaking up in 1985. The group would reunite on and off over the years following.

In 2012, The J. Geils Band toured without Geils' involvement, leading the founding guitarist to file an unsuccessful lawsuit against group members Richard Salwitz, Danny Klein, Peter Wolf and Seth Justman over use of the band's name for a tour without him. Geils left the band permanently following this incident.