The House passed a bill to place communication by electronic mail, paging devices, car telephones and data transmitters under the same privacy protection as first-class mail. Rep. Pat Swindall (R-Ga.) said that the measure also outlines due process for authorities to follow when they intercept such communications. A prosecutor would have to demonstrate probable cause to suspect criminal activity and get court permission to search electronic files. The change is backed by both the Reagan Administration and civil libertarians. A similar bill is pending in the Senate.