I was actually trying to find something else, but this is pretty interesting. Prior to 1974 "self-certication" had always been acceptable, but evidently became a problem in the 1970s and that rule needed to change...
From
Docket No. 19356; FCC 74-113
Adopted: February 6, 1974.
Released: February 15, 1974.
Bilateral Certification
9. ’The Commission has in the past provided for a “self-certification” procedure for most equipment operated without individual license under Parts 15 and 18 of our rules. Such “self-certification” merely required the user to perform certain engineering tests on the device and attach a label to his device “certifying” that the device had been tested and found to comply. In many cases, notably with respect to receivers and low power communication devices under Part 15, the manufacturer performed these tests voluntarily as a service to his customer and labeled the equipment.
This system of “self-certification” has not proved entirely satisfactory in practice. Accordingly, we will now require that where the rules call for the equipment to be certificated, the equipment must receive such certification from the Commission prior to marketing. A grant of certification will be based on a review of test data and other relevant Information specified in the rules adopted herein and required in the substantive Part of the rules unwhich the equipment operates......
10. Other comments objected to bilateral certification on the grounds that Increased costs would be incurred...... Accordingly, the only increase in cost to the manufacturer, is the administrative cost of filing the application for certification and deferring marketing until the Commission's grant of certification is received.
On the other hand bi lateral certification is imposed to carry out the intent of the authorizing legislation (47 UB.C. 302) to provide reason able assurance that equipment placed in the hands of the public is not likely to become a source of harmful interference. Under these conditions, the Commission cannot accept the objection to bilateral certification because of alleged increased cost.
....... It was argued therefore that bilateral certification was not necessary and should not be imposed on equipment...