INDIANAPOLIS (AP) — Investigators trying to determine what caused a deadly Indianapolis bus crash last month might not have many records to check because Indiana lacks a mechanism to oversee such vehicles.

The Indianapolis Star reports the bus owned by Colonial Hills Baptist Church was inspected in 2010, but there's no public record showing it was inspected after that.

Federal law allows such buses to be inspected by private companies and does not require owners to submit proof of inspections.

The crash occurred July 27 as the bus returned from a camp in Michigan. The driver told police the brakes on the bus failed as he exited an interstate about a mile from the church.

Youth pastor Chad Phelps, his pregnant wife, Courtney, and chaperone Tonya Weindorf died. Dozens were injured.